Oral Presentations - Wiley Online Library

SARS abstracts

ORAL PRESENTATIONS PATEY PRIZE SESSION

O1 Neoadjuvant chemotherapy induces changes in expression of breast cancer resistance protein that predict disease free survival in breast cancer B. Kim1,3 , B. J. Williams2 , H. Fatayer3 , A. M. Hanby1,2 , K. Horgan3 , J. L. Thorne1 , E. M. A. Valleley1 , E. T. Verghese1,2 , T. A. Hughes1 1 Leeds Institute of Molecular Medicine, University of Leeds, Leeds, UK, 2 Department of Histopathology, St. James’s University Hospital, Leeds, UK, 3 Department of Breast

Surgery, Leeds General Infirmary, Leeds, UK Introduction: Three main xenobiotic efflux pumps have been implicated

in modulating breast cancer response to chemotherapy. These are Pgp (P-glycoprotein, multidrug resistance protein-1), MRP1 (multidrug resistanceassociated protein 1), and BCRP (breast cancer resistance protein). We aimed to investigate expression of these proteins before and after neoadjuvant chemotherapy (NAC) to determine whether levels define response to NAC or subsequent survival. Methods: Paraffin embedded tissue was collected representing matched pairs of core (pre-NAC) and surgical specimens (post-NAC) from 45 patients with invasive ductal carcinomas (follow-up range 3-8.8 years). NAC regime consisted of anthracyclines +/− taxanes. Immunohistochemistry was performed. A computer-aided scoring protocol was developed and validated against 2 independent observers (intra-class correlation coefficient 0.83 and 0.82). Results: Pgp and MRP1 expressions were significantly upregulated after exposure to NAC (p = 0.0024 and p < 0.0001). BCRP expression showed more variation in response: individual cases showed either down- (41%) or upregulation (59%) after NAC. Pre- or post-NAC expression of Pgp, MRP1 or BCRP did not correlate with clinical response to NAC. However, expression of BCRP post-NAC, but not pre-NAC, correlated with disease free survival (DFS): significantly longer 5-year DFS was seen in patients with low expression compared to high expression (80% vs. 40%; Log rank p = 0.007). Conclusion: High expression of BCRP after treatment with NAC is an adverse event, and investigating mechanisms that control BCRP induction and repression may improve NAC efficacy.

O2 The significance of oestrogen receptors in oesophageal cancer development W. Al-Khyatt, C. Tufarelli, R. Khan, S. Y. Iftikhar School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Uttoxeter Road, Derby Introduction: A recent nested case-control study within a UK cohort and

meta-analyses suggested that the use of menopausal hormone therapy has been associated with reduced risk of oesophageal cancer (OC). In this study, the potential significance of oestrogen and its receptors (ER) as therapeutic biomarkers in OC is investigated. Methods: Following local REC approval, the OC cell lines, OE33 and OE19, were used to study the effect of ER modulators on cell proliferation using 5-bromo-2 -deoxyuridine (colorimetric) assay. ERα and ERβ expression profiling in paired normal oesophageal mucosa and tumour tissues (n = 34) was performed using quantitative Real Time Polymerase Chain Reaction (RTPCR). Correlation between expression levels of ER with the clinico-pathological features for OC was also determined.

 2013 British Journal of Surgery Society Ltd Published by John Wiley & Sons Ltd

Results: There was a significant dose dependant inhibition of proliferation in OE33 and OE19 OC cell lines by a highly selective ERα antagonist (MPP) and ERβ specific antagonist (PHTPP) (p < 0.05). RT-PCR analysis revealed that ERα and ERβ mRNA expression was significantly higher (p < 0.05) in tumour tissues relative to their paired normal mucosa. Moreover, expression of ERα and ERβ in the tumour tissue samples correlated inversely with survival outcome (p < 0.05). Finally, up-regulation of ERα correlated with higher pathological T stage (p < 0.05) and lymph node metastasis (p < 0.05), while ERβ up-regulation

correlated with positive vascular invasion (p < 0.05). Conclusions: There is a significant up-regulation of ER mRNA in OC which

has an adverse prognostic correlation. The inhibition of OC cell lines by highly selective ER modulators indicates that ER may have a potential therapeutic significance in the treatment of OC. Take-home message: In this study, it has been demonstrated that upregulation of ER has an unfavourable relationship with survival and pathological features of OC. Furthermore, selective blocking of ER seems to inhibit OC cell proliferation. Therefore, ER system may provide an additional novel target for the treatment of OC.

O3 An omega-3 rich lipid emulsion is associated with improved clinical outcome in patients with severe acute pancreatitis: A randomised double-blind controlled trial D. Al-Leswas, A. Arshad, A. Eltweri, W. Y. Chung, O. Al-Taan, C. Pollard, M. Metcalfe, A. R. Dennison Hepatobiliary and Pancreatic Surgery, University Hospitals of Leicester, Leicester, United Kingdom Introduction: Early deaths in patients with severe acute pancreatitis (SAP)

are usually caused by multiple organ failure driven by acute inflammation. Omega-3 fish oil (n-3 FO) has proven anti-inflammatory properties. We aimed to investigate the effects of n-3 FO in SAP patients. Methods: We conducted a randomised double-blind controlled trial in patients with SAP. The two groups received a lipid emulsion with (n-3 FO group) or without (control group) fish oil in conjunction with standard care. Infusions were initiated within 72 hours of symptom onset and for a maximum of 7 days. Organ failure, ITU/HDU admission, length of stay, septic complications and mortality were recorded. Results: Fourty-four patients were included with equal numbers (22) in each group. 19/22(86%) of the control group and 14/22(64%) patients in the n-3 FO group developed one or more organ failure with 13/22 (59%) of the control group and 6/22(27%) of the n-3 FO group developing new organ failure (p = 0.033) Eleven patients (50%) in the control group vs 5/22(23%) in the n-3 FO group required admission to the ITU/HDU, p = 0.060. The fish-oil group had significantly shorter ITU/HDU and hospital stay (1+/−3 vs 7+/−11, p = 0.029 and 12+/−6 vs 21 +/−13, p = 0.043, respectively). Septic complications occurred in 8(36%) patients of the fish-oil group and 11(50%) of the non-fish oil group, p = 0.361. There were 2 deaths (1 in each group). Conclusion: Fish oil based lipid emulsion is associated with fewer organ failures; better recovery and shorter ITU/HDU and hospital stay in patients with SAP. A larger multicentre trial is warranted. Take-home message: Fish oil emulsions improve the clinical outcome in patients with severe acute pancreatitis

British Journal of Surgery 2013; 100 (S4): 2–49

SARS abstracts

O4 Identification of IL8 and TIMP4 as molecular phenotypic descriptors of breast capsular contracture formation using informatics analysis of the whole genome transcriptome D. J. T. Kyle1 , A. G. Harvey1 , B. Shih1 , K. T. Tan1 , I. H. Chaudhry4 , A. Bayat1,2,3 1 Plastic & Reconstructive Surgery Research, Manchester Interdisciplinary Biocentre, University of Manchester, UK, 2 Department of Plastic and Reconstructive Surgery,

University Hospital South Manchester Foundation Trust, Wythenshawe Hospital, Manchester, UK, 3 The University of Manchester, Manchester Academic Health Science Centre, University Hospital South Manchester Foundation Trust, Wythenshawe Hospital, Manchester, UK, 4 Department of Laboratory Medicine, Central Manchester NHS Foundation Trust, Manchester, UK Introduction: Breast capsular contracture formation following silicone implant

augmentation/reconstruction is a common complication that remains poorly understood. Several candidate genes have been associated with this condition; however, there are no published studies to date that have utilised whole genome microarrays in identifying biomarkers. The aim of this study was to identify potential biomarkers implicated in breast capsular contracture formation by using whole genome arrays. Methods: Biopsy samples were taken from 18 patients (23 breasts) with Baker Grade I and II (classified as mild contracture) and Baker Grade III and IV (classified as severe contracture). Whole genome microarray was performed and 6 significantly dysregulated genes were identified for validation with quantitative reverse transcriptase polymerase chain reaction (QRT-PCR). Haematoxylin and eosin (H&E) and quantitative immunohistochemistry (IHC) analysis was then performed on the breast capsules. Results: Microarray results showed that the genes ACAN, TIMP4, and TNFSF11 were significantly downregulated in severe contracture; while, MMP12, SAA1, and IL8 were significantly upregulated when compared to mild contracture. The dysregulation of ACAN, TNFSF11, TIMP4 and IL8 was validated by QRT-PCR. (p values < 0.05). Quantitative IHC showed increased expression of IL8 and MMP12 in severely contracted capsules (p < 0.05), and decreased expression of TIMP4. No statistical significance was found between Baker grades for ACAN, TNFSF11 and SAA1. Conclusion: For the first time, this study has shown a number of unique biomarkers of significance in capsular contracture formation. IL8 and TIMP4 may serve as potential key diagnostic, therapeutic and prognostic biomarkers in capsular contracture formation. Take-home message: Breast capsular contracture formation is the most common complication post breast augmentation/reconstruction and its pathoetiology is still not clearly understood. This paper describes the results of the first whole genome microarray ever performed on breast capsules, verified with QRT-PCR and quantitative IHC and H&E, which found IL8 and TIMP4 as two potential key diagnostic, therapeutic and prognostic biomarkers in capsular contracture formation.

O5 Patey Prize winner Availability of T cell help determines alloantibody levels and graft outcome in a murine model of antibody-mediated rejection M. Chhabra, C. J. Callaghan, S. Rehakova, M. C. Negus, E. M. Bolton, J. A. Bradley, G. J. Pettigrew Department of Surgery, University of Cambridge

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was determined by anti-H-2Kd ELISA. CB57BL/6 Rag2−/− recipients that lack both T and B cells were used as controls. Results:Reconstitution of TCR−/− recipients of BALB/c hearts with 105 TCR75 T cells resulted in strong alloantibody responses and acute graft rejection (MST 9 days, n = 9). Reconstitution with 103 CD4 T cells resulted in much more modest alloantibody production, but was nevertheless associated with endothelial complement deposition, development of progressive allograft vasculopathy and gradual graft loss (MST 50 days, n = 6). In contrast, BALB/c hearts survived indefinitely, with minimal allograft vasculopathy, when transplanted into control Rag2−/− recipients reconstituted with either high or low numbers of TCR75 T cells. Notably, passive transfer of Rag2−/− recipients with immune serum from TCR−/− recipients reconstituted with 105 TCR75 T cells resulted in acute heart graft rejection and florid intragraft complement deposition. Conclusion: The magnitude of the alloantibody response determines whether humoral alloimmunity effects acute or chronic rejection, and is in turn determined by the availability of T cell help. (MST – mean survival time) Take-home message: The availability of T cell help is a critical factor in determining the size of the alloantibody response, and its consequent ability to mediate acute or chronic graft damage in a newly-developed model of antibody-mediated rejection.

O6 Iron chelation in the treatment of oesophageal adenocarcinoma – in-vivo action of deferasirox on a xenograft model S. J. Ford1 , M. R. Bedford1 , O. Tucker2 , T. Iqbal1 , D. Alderson2 , C. Tselepis1 1 Cancer Research UK Institute for Cancer Studies, University of Birmingham, Birmingham, UK, 2 University Hospital Birmingham, Birmingham, UK

Introduction: The malignant progression of Barrett’s metaplasia to

oesophageal adenocarcinoma (OAC) is associated with altered expression and function of the pertinent cellular iron transport proteins. These alterations result in increased cellular iron loading which is likely to drive cellular proliferation; a key hallmark of cancer. This is further supported by a wealth of data demonstrating that iron chelators cause cell cycle arrest and apoptosis. The aim was to determine if the clinically established iron chelator Deferasirox has in-vivo anti-neoplastic activity by utilising a xenograft model of OAC. Methods: A murine model of OAC was produced by xenografting OE33 and OE19 OAC cells subcutaneously into NOD-SCID mice. Deferasirox was gavarged as an oral agent on alternate days for 3 weeks. The mice were culled and the xenograft, liver, spleen, heart and blood harvested for analysis. All animal work was performed under Home Office approved conditions. Results: Oral Deferasirox significantly impaired xenograft growth compared to controls; 43% (p = 0.0061) and 42% (p = 0.05) average reduction in xenograft weight for OE33 and OE19 respectively. Deferasirox treatment was well tolerated with no change in average mouse weight compared to control. Crucially, iron chelation did not induce systemic anaemia or major organ dysfunction. Conclusion: The clinically established oral iron chelator Deferasirox appears to have significant in-vivo anti-neoplastic effects in a murine xenograft model of OAC. Furthermore, after three weeks of dosing without oral iron supplementation, no systemic signs of anaemia were observed. Oral iron chelators should be considered as anti-neoplastic agents in human trials. Take-home message: Clinically established iron chelators exhibit potent anti-neoplastic effects without systemic iron stripping. Iron chelators should be trialled as an adjunct to standard chemotherapeutic agents in the treatment of oesophageal adenocarcinoma.

Introduction: The mechanisms by which alloantibody affects acute or chronic

allograft rejection remain unclear. Here we hypothesise that the availability of T cell help determines the outcome of antibody-mediated rejection. Methods: MHC-mismatched BALB/c hearts were transplanted into T celldeficient (TCR−/−) CB57BL/6 recipients. T cell help was provided by transfer of either high (105 cells) or low (103 cells) numbers of TCR-transgenic TCR75 CD4 T-cells that recognise Class I donor H2-Kd antigen as selfrestricted processed peptide via the indirect pathway. Alloantibody production


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SARS abstracts

effects of PSC. This is associated with restoration of E-cadherin expression and reduction in cancer cell invasion. Conclusions: HDACi thus represent a promising therapeutic agent for targeting pancreatic cancer stroma, thus disrupting the cancer- stroma cross-talk. Take-home message: Targeting pancreatic cancer stroma is a pathway that should be well investigated and offers an opportunity to tackle pancreatic cancer in a novel way.

O7 Generation of HLA-specific humanised mice using bone marrow-derived haematopoietic stem cells from cadaveric organ donors K. M. Elliott1 , T. M. Conlon1 , M. Negus1 , F. J. Rouhani2 , L. Vallier2 , E. M. Bolton1 , J. A. Bradley1 , G. J. Pettigrew1 , K. Saeb-Parsy1 1 Department of Surgery, University of Cambridge, 2 Laboratory of Regenerative

Medicine, University of Cambridge Introduction: ‘Humanised’ mice reconstituted with a functional immune

compartment are an invaluable tool in the study of the immune response to human cells and tissues and can be generated using haematopoietic stem cells (HSCs) from a variety of sources. However, bone marrow (BM) from cadaveric organ donors represents the only potentially abundant source of HSCs of specified HLA type. We therefore examined the ability of BM-derived HSCs from cadaveric organ donors to generate a humanised mouse model to investigate human responses to alloantigens. Methods: Bone marrow was aspirated from the lumbar vertebrae and iliac bones of human cadaveric donors after other organs were retrieved for transplantation and the mononuclear fraction was separated using Ficoll gradient and frozen at −80◦ C. After thawing, live CD34+ HSCs were isolated using magnetic beads and adoptively transferred into sub-lethally irradiated immmunodeficient NOD/SCID/IL2rγ-/- mice. Engraftment was assessed by flow cytometric analysis of peripheral blood samples at weekly intervals. Results: Bone marrow was successfully harvested from cadaveric donors that proceeded to donation after either brain death or circulatory death (oldest donor aged 78). Post-thaw viability of the CD34+ fraction was routinely >80% and NSG mice were successfully reconstituted with CD45+ human B (70.1%), CD4 (3.2%) and CD8 (2.57%) T lymphocytes by 8 weeks. Conclusion: Our data show that BM-derived HSCs survive circulatory arrest for several hours and maintain their engraftment potential in immunodeficient mice. This model enables the generation of HLA-specific humanised mice, using a readily available source of HSCs, to investigate human immune responses to alloantigens. Take-home message: Bone marrow from cadaveric organ donors is a viable source of haematopoietic stem cells for the generation of humanised mice.

O8 Targeting pancreatic cancer stroma by HDAC inhibitors M. A. Ghallab, G. Rosignoli, I. S. Escrig, H. C. Hurst, I. R. Hart, S. Bhattacharya, H. M. Kocher Barts Cancer Institute, Queen Mary University

O9 SIFT-MS analysis of headspace vapour from gastric content for the diagnosis of gastro-oesophageal cancer S. Kumar, J. Huang, G. B. Hanna Division of Surgery & Cancer, Imperial College London Introduction: In the UK, gastro-oesophageal cancer has a five-year survival

rate of 13%. The key to improving poor survival lies in earlier diagnosis. The identification of disease-specific Volatile Organic Compounds (VOCs) has generated much scientific and clinical interest; the ultimately translational application is the development of non-invasive diagnostic tests. We report the first investigation of VOCs through headspace analysis of gastric content using Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS). We hypothesise the concentration of VOCs in gastric content from gastro-oesophageal cancer patients differs from controls. Methods: Patients were recruited through our Endoscopy Unit. All patients had fasted for at least 6 hours. Gastric content samples were obtained from those undergoing oesophago-gastro-duodenoscopy (OGD). Gastric content was captured in a suction trap during the procedure and aliquoted to 10mls. Samples were analysed in multi-ion-monitoring (MIM) mode using a Profile-3 SIFT-MS instrument. Results: Forty-two gastric content samples were analysed (gastro-oesophageal cancer n = 19, positive controls n = 12, healthy controls n = 11). Seven VOCs (acetone, formaldehyde, acetaldehyde, hexanoic acid, hydrogen sulphide, hydrogen cyanide and methyl phenol) demonstrated statistically significant (p < 0.05) differences between cancer and healthy groups. Receiver operating characteristics (ROC) analysis was applied for the combined VOCs of acetaldehyde, formaldehyde, hydrogen sulphide and methyl phenol to discriminate cancer from healthy controls. The area under curve (AUC) is 0.9. Conclusions: This is the first study to perform gastric content headspace analysis from gastro-oesophageal cancer patients and controls. Further studies are necessary to understand the biochemical basis for the observed differences in VOCs within the gastro-oesophageal cancer group. Take-home message: Volatile Organic Compound Analysis represents a promising area of development for novel clinical diagnostics.

Introduction: Recent work in our lab has shown that Retinoic Acid (RA)

successfully rendered pancreatic stellate cells (PSC) quiescent consequently inhibiting cancer growth. RA signalling acts in conjunction with is a direct Histone De-acetylase (HDAC). Histone De-acetylase inhibitors (HDACi) are a potential therapeutic agent for pancreatic cancer. Therefore HDACi, either alone, or in combination with RA, could be used to modulate stellate cells and, in turn, affect pancreatic cancer cell behaviour. Methods: Vorinostat, Valproic acid and Trichostatin A were used to treat pancreatic cancer and stellate cells. Western blot, DNA content analysis and proliferation assay were performed on 2D culture. The cancer cells (with or without PSC) were treated in the 3D collagen/matrigel organotypic culture model, to study the physiological relevance of the HDACi in presence of the desmoplastic tumour microenvironment. Results: Acetylation of Histone-3 (H3K9) occurs in a dose-dependent manner in both cancer cells and stellate cells with all three HDACi resulting in cellcycle arrest. Further analysis of the Sub-G1 portion of the cell-cycle data as well as proliferation assay showed stellate cells to be more susceptible than cancer cells at the physiologically achievable doses. In 3D organotypic cultures, when cancer cells are cultured on their own HDACi have no effect. However, when co-cultured with PSC, the HDACi abrogate the cancer cell proliferative


O10 Reduced expression of semaphorin (SEMA4D) and Plexin B in breast cancer is associated with poorer prognosis, and the potential linkage with oestrogen receptor F. A. Malik1,2 , L. Ye1 , W. G. Jiang1 1 Metastasis & Angiogenesis Research Group, Cardiff University School of Medicine, Cardiff, CF14 4XN, UK; 2 Department of Biosciences, COMSATS Institute of

Information Technology, Islamabad, Pakistan Introduction: Involvement of semaphorin-4D and their receptor proteins of

the Plexins B family (Plexin-B1,-B2 and -B3) in solid tumours suggests their potential implications in breast cancer. In the present study, expression of SEMA4D and Plexin-Bs were examined in the breast cancer cohort. Methods: Expression of semaphorin-4D and Plexin-Bs were examined in 127 tumours together with 22 normal mammary tissues using quantitative PCR together with clinical and pathological patient data. Expression of SEMA4D

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SARS abstracts

and PLXNB1 were determined in MCF-7 and MDA-MB-231 cells treated with selected oestrogen receptor modulators (SERMs). Results: Expression of semaphorin-4D, plexin-B1 and -B2 were markedly reduced in tumours with local recurrence, compared to disease free patients. Reduced semaphorin-4D expression was associated with poorer disease free survival, being 111.6 months (96.5–126.7, 95%CI), p = 0.033 when compared to 144.0 months (130.8–157.3, 95%CI) of patients with higher expression. Reduced expression of plexin-B1 was seen in tumours with poorer differentiation and was associated with poorer overall survival and disease free survival. No similar association was seen in relation to plexin-B2 and plexin-B3. Higher expression of semaphorin-4D and plexin-B1 was observed in ERα positive compared with ER-α negative tumours. Expression of these molecules was also largely regulated in breast cancer cells exposed to SERMs. Conclusions: Decreased SEMA4D, PLXNB1 and PLXNB2 expressions are associated with local recurrence and poor prognosis. Response to SERMs showed a potential implication of these molecules in the diagnosis and differential treatment of the disease with consideration of ER status. Take-home message: These receptor and ligand molecules (PLEXIN B1 and SEMA4D) are of prognostic importance in breast cancer. Regulation of their expression is also influenced by oestrogen receptors so treatment strategies can be devised by early screening of these molecules expression.

O11 Global genetic alterations from primary and node to metastasis: New insights into breast tumour reprogramming J. C. Bolger, D. P. McCartan, A. Fagan, E. Hughes, J. McBryan, P. O’Gaora, A. D. Hill, L. S. Young Endocrine Oncology Research, Royal College of Surgeons in Ireland, Dublin Introduction: The development of breast cancer resistance to endocrine

therapy results from altered cellular plasticity causing the emergence of a poorly differentiated, hormone-independent tumour. The underlying mechanism of how ER+, endocrine sensitive tumours can activate these adaptive mechanisms remains unresolved. We hypothesise that cellular reprogramming can occur as a result of long-term endocrine treatment, manifesting clinically as tumour recurrence. We adopted a global approach to define transcriptional networks significantly elevated in metastatic tumours. Methods: We developed a novel method of RNA sequencing utilising paraffinembedded tissue, determining the gene expression profile of matched primary, nodal and metastatic tissue of three ER + patients (one luminal A, one luminal B1, one luminal B2) who developed recurrence on endocrine therapy. Pathway analysis and transcription network mapping was performed. Target expression was confirmed in an endocrine resistant in vivo model, a TMA of 1,100 patients and in a cohort of matched primary/recurrence patients by western blotting, immunohistochemistry and PCR. Results: 209 genes were uniquely elevated in the metastatic context. Pathway analysis showed up-regulation of developmental pathways (WNT, TGFbeta), growth factor signalling (MAPkinase), adhesion molecules and junction adherens. Transcription factors identified involved in de-differentiation included Myc, SMAD2, ESR, TCF3, CUX1 and CLOCK. These were validated in xenograft and patient samples. Conclusion: Using novel global analysis, we identified a number of transcription factors which may establish de-differentiation following endocrine treatment. This represents a fundamental shift in studying the development of resistance to endocrine therapy: endocrine treatment may drive dedifferentiation and recurrence of an initially well-differentiated, steroidresponsive tumour. Take-home message: Novel global RNA sequencing has uncovered a number of transcriptional networks elevated in metastases compared with primary breast tumours.


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O12 Activation of HIF1α Promotes androgen lindepent prostate cancer cell growth G. B. Tran, F. Lo, A. Ramos-Mantoya, S. Menon, M. Osborne, J. Hadfield, A. Warren, C. Massie, P. Maxwell, I. Mills, D. Neal Addenbrookes/Cambridge University, lab 120 Uro-oncology Group, CRI, CRUK, Cambridge Introduction: An established consequence of hypoxia is activation of the Hypoxia-Inducible-Factor-1α (HIF1α) transcriptional pathway. A recent study

has reported that prostate cancer (PCa) cells derived from patients with poor prognoses exhibit a constitutively hypoxic phenotype. However, the role of HIF1α in PCa remains unclear. Methods: PCa cell lines (LNCaP, PC3, C42, C42b, LNCaP-bic) were used for western blotting, matrigel invasion, expression profiling, and ChIP studies. Stable LNCaP subclones generated by retroviral infection of constitutively active HIF1α or Empty vector and Luciferase were used for bioluminescence xenograft studies. Hypoxic experiments were conducted using a Ruskinn hypoxic workstation. Results: Androgen independent PCa cells (C42b, C42 and PC3) have constitutive expression of HIF1α compared to androgen dependent LNCaPs. Induction of HIF1α expression in LNCaPs either by hypoxia or in stable subclones increases cellular proliferation and invasion. Furthermore, HIF1α promotes androgen independent cell growth and resistance to Bicalutamide. Microarray studies demonstrate that HIF1α changes the AR transcriptional signature. Indeed, HIF1α alone recapitulates over 18% of the differential gene expression normally induced by androgen. Functional experiments using AR ChIP show differential recruitment of the AR in hypoxia. Finally, xenografts confirm continued growth by the HIF1α expressing tumours despite castration. Conclusion: HIF1α has an important role in the adaptive cellular response that is more conducive to survival in the castrate setting. HIF1α provides an alternative pathway that can be targeted therapeutically in the quest for effective management of hormone refractory disease. Take home message: Expression of HIF1α confers androgen independent growth advantages invitro and invivo in prostate cancer. Further investigation of the interplay between the HIF and AR signalling pathways could elucidate much needed alternative therapeutic strategies in advanced prostate cancer.

O13 Therapeutic fatty acid synthase inhibition can be monitored using 11C acetate pet in a xenograft model of prostate cancer G. L. Shaw, D. Lewis, J. Boren, A. Ramos-Montoya, D. Soloviev, K. Brindle, D. Neal Cambridge University Introduction: Fatty acid synthase (FAS) is upregulated in prostate cancer at

mRNA and protein levels. A preclinical understanding of the effects of inhibiting FAS will greatly assist the design of future clinical trials. Methods: Prostate cancer C42b cell xenografts were generated in NodSCID-gamma mice. The mice were dosed daily by oral gavage with 3mg/kg GSK2194069, a novel FAS inhibitor or vehicle. Mice bearing xenografts were injected with 11C acetate and imaged using PET CT before and after oral administration of GSK2194069 3mg/kg. Similar animals were administered 14C acetate before and after GSK2194069 administration. Results: Tumour growth was inhibited in those mice dosed with GSK2194069 Mean tumour size after 5 weeks growth was 595.0 ± 171.2mm3 (N = 6) in the vehicle group (and 106.2 ± 26.23mm3 (N = 5) in the GSK2194069 treated group (p = 0.037 two-tailed unpaired t-test). There was no significant weight loss in the GSK2194069 treated cohort and no adverse effects noted.

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The effect of GSK2194069 in decreasing acetate uptake was seen with scintillation detection of 14C-acetate in the lipid phase of C42b xenograft tumours by 56% 2 hours after dosing with GSK2194069. Inhibition of FAS by GSK2194069 resulted in a decrease in acetate signal in all animals (n = 7) and by a median of 43 percent (p < 0.05, paired t-test). Conclusion: PC xenograft growth can be inhibited with GSK2194069 a novel fatty acid synthase inhibitor. The effects of GSK2194069 on FAS activity can be monitored non-invasively by imaging with 11C acetate PET. Take home message: Therapeutic fatty acid synthase inhibition is on the horizon. Clinical trials will be facilitated by the ability to monitor FAS inhibition using 11C acetate PET.

O14 Design of novel nanocomposite nerve conduits T. Sedaghati1 , G. Jell1 , A. Mosahebi1,2 , P. Butler1,2 , A. M. Seifalian1 1 Centre for Nanotechnology & Regenerative Medicine, UCL Division of Surgery & Interventional Sciences, University College London, London, UK, 2 Department

of Plastic and Reconstructive Surgery, Royal Free Hampstead NHS Trust Hospital, London, UK Introduction: Despite huge advances in the field of tissue engineering, artificial

nerve conduits have met with limited success and certainly do not match the outcomes achieved by nerve auto-grafting techniques. We are developing a


new nanocomposite polymers based on incorporating POSS nanoparticles into various polyesters. The bio-stable form of this family of nanocomposites, known as UCL Nano, has been successfully implanted in human in the form of a small calibre bypass graft, lacrimal duct conduit, and more recently as the world’s first synthetic trachea. Here we investigate the use of a degradable form of this proven polymer (NanoBio) for nerve conduit fabrication. Method: Nerve conduits were produced by either solvent casting (SC) or particulate leaching (PL) techniques. Physio-chemical properties of the conduits were assessed by tensile strength, scanning electron microscope (SEM), permeability and water contact angle (WCA). To assess biocompatibility of conduits, Schwann cells were seeded into the conduits and their metabolic activity was assessed by AlamarBlue assay. Results: Both conduits showed sufficiently high mechanical properties to be used as nerve conduits. SEM showed significant porosity achieved on SC conduits compared to non-porous PL conduit. This was further confirmed by results obtained by permeability test. Porosity and pore related properties, such as size and morphology, could be influenced by porogen selection and its concentration within polymer solutions. The surface wetability is mostly affected by surface chemistry in which they may affect certain protein attachment to the surface of the construct and consequently cellular behaviour such as adhesion, proliferation and differentiation. AlamarBlue assay confirmed the biocompatibility of these conduits with seeded Schwann cells. Conclusion: Based on the great results obtained by this study, we aim to further investigate the potential of these fabricated conduits on nerve tissue engineering by testing them on animal model.

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mixed effects regression model to explore further the association between the length of stay and the concentration of cytokines. Conclusion: Omega-3 fish oil emulsion modifies the acute inflammatory response evidenced by reduction in pro-inflammatory cytokine concentrations in patients with SAP. These modifications are associated with a better and quicker recovery. Take-home message: Omega-3 fish oil modulate the inflammatory response in patients with SAP, and results in a better and quicker recovery.

RSM SECTION OF SURGERY MIA PRIZE O15 FOXO3a expression in colorectal cancer: A promising biomarker of micrometastases A. Bruce, M. Bullock, N. Curtis, R. Sreekumar, J. Primrose, G. Thomas, A. H. Mirnezami

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University of Southampton Cancer Research UK Centre Introduction: The Forkhead/winged helix box class O3a (FOXO3a) tumour

suppressor belongs to a conserved family of transcription factors, and orchestrates critical programs of gene expression involved in differentiation, apoptosis, and DNA damage responses. The aim of the present study was to investigate the role of FOXO3a in human colorectal cancer (CRC). Methods: Formalin fixed resection specimens from 20 benign, 164 primary, and 58 matched liver metastases were used to generate tissue microarrays. Triplicate cores of 1 mm diameter were taken from representative areas and immunohistochemical staining for FOXO3a conducted. Semi-quantitative scoring was carried out blindly by two investigators one of whom was a clinical pathologist. Results: FOXO3a expression was significantly reduced with advancing cancer stage (p < 0.0005) and when compared with normal and adenomatous tissue. 33 early stage (I/II) non-recurrent primary tumours showed significantly higher FOXO3a expression when compared with 33 stage-matched recurrent tumours. When stratified according to high and low FOXO3a expression, mean disease free survival in the Low FOXO3a expressing group was 28 months (95% CI 15.8-50.6) compared to 64 months (95% CI 52.9-75.4) in the high FOXO3a expressing group (p = 0.001). No difference between FOXO3a expression was noted between primary tumours with synchronous and metachronous recurrence and their matched liver metastases. Conclusions: FOXO3a levels are reduced during CRC progression, and low levels in the primary tumour associated with recurrent disease. Low FOXO3a levels may represent a novel biomarker of nodal and distant disease spread.

O16 Evaluation of the acute inflammatory response to omega-3 fatty acids in patients with severe acute pancreatitis: A randomised controlled trial D. Al-Leswas, W-Y. Chung, A. Eltweri, A. Arshad, C. Pollard, M. Metcalfe, A. Dennison Hepatobiliary and Pancreatic Surgery, University Hospitals of Leicester, Leicester, United Kingdom Introduction: Polyunsaturated fatty acids (PUFA), especially omega-3 PUFA,

like eicosapentaenoic (EPA) and docosahexaenoic acids (DHA), which are major components of fish oil, have demonstrated potent anti-inflammatory and immunomodulatory activities in animal and human studies. We investigated the effects of omega-3 PUFA on inflammatory cytokine concentrations in patients with severe acute pancreatitis (SAP). Methods: Forty-four patients, with predicted SAP, were randomly assigned to receive either a 50:50 mixture of medium-chain fatty acids and soybean oil (control group, n = 22) or a 50:40:10 mixture of medium-chain fatty acids, soybean oil and fish oil (study group, n = 22). Lipid mixtures were infused for a maximum of 7 days and circulating serum cytokine concentrations (IL-6, IL-8, TNF-α, IL-18, ICAM-1, IL-10) were measured at 6 time points from baseline to day 7 of the infusion using a multiplex cytokine array (MSD systems). Statistical analysis was performed using the Mann–Whitney test to compare means. Results: Serum IL-6 concentration showed a significant reduction on days 2,3,5and 7 (p = 0.018, 0.004, 0.039, 0.039) in the fish oil group. This reduction in concentration had a significant correlation with ITU/HDU and hospital length of stay, p = 0.029 and p = 0.009 respectively. At each time point of analysis, IL-8, TNF-α, IL-18 and ICAM-1 serum concentrations displayed a tendency towards reduction (p > 0.05). Results will be presented from a linear


Genome analysis of colorectal cancers in British Bangladeshis identifies early onset and a high prevalence of rbfox1 deletion compared to Caucasians N. Sengupta1 , C. Yau2 , A. Sakthianandeswaren3 , D. Mouradov3 , P. Gibbs3 , N. Suraweera1 , J-B. Cazier4 , G. Polanco-Echeverry1,5 , A. Ghosh1 , M. Thaha1,6 , S. Ahmed6 , R. Feakins7 , D. Propper8 , S. Dorudi1 , O. Sieber3,9 , A. Silver1 , C. Lai1 1 Centre for Digestive Diseases, Blizard Institute of Cell and Molecular Science, Barts

and The London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark St, Whitechapel, London E1 2AT, 2 Department of Mathematics, South Kensington Campus, Imperial College London, London SW7 2AZ, 3 Ludwig Colon Cancer Initiative Laboratory, Ludwig Institute for Cancer Research, Parkville, VIC 3050, Australia, 4 Bioinformatics and Statistical Genetics, 5 Present address: Genomic Services, Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford, OX3 7BN, 6 Academic Surgical Unit, 7 Department of Pathology, The Royal London Hospital, 80 Newark St, Whitechapel, London E1 2ES, 8 St Bartholomew’s Hospital, Gloucester House, Little Britain, London, UK, 9 Faculty of Medicine, Dentistry and Health Sciences, Department of Surgery, University of Melbourne, Parkville, VIC 3050, Australia. Introduction: Prevalence of colorectal cancer (CRC) in the British Bangladeshi

population (BAN) is low compared to British Caucasians (CAU). Genetic background may influence mutations and disease features. Methods: We interrogated BAN CRC genomes using mutation profiling and high-density single nucleotide polymorphism arrays and compared findings to CAU CRCs. Results: Age of onset of BAN CRC was significantly lower than for sporadic CAU patients (p = 3.0 × 10−5 ) and not due to Lynch syndrome or polyposis. KRAS and BRAF mutations were comparatively rare with significantly fewer KRAS mutations (5.4%) compared to CAU MSS CRCs (25%; p = 0.04) and no BRAF mutations (CAU CRCs, 12%). Array data revealed patterns of gains (chromosome 7 and 8q), losses (8p, 17p and 18q) and LOH (4q, 17p and 18q) similar to CAU CRCs. A small deletion on chromosome 16p13.2 involving the RNA-binding alternative splicing factor RBFOX1 only was found in significantly more BAN (50%) than CAU CRCs (15%) cases (p = 0.04). Novel RBFOX1 mutations were identified in CRC cell lines and tumours; mRNA and protein expression was also reduced. Conclusions: Mutations of KRAS and BRAF were rare in BAN CRC. Loss of RBFOX1 may explain the anomalous splicing activity associated with CRC and warrants further investigations. Take-home message: A small deletion on Chromosome 16 is significantly more in Bangladeshi patients with colorectal cancer compared to Caucasian patients.

O18 Evaluation of one step nucleic acid amplification (OSNA) molecular assay for intra-operative diagnosis of sentinel lymph node metastasis S. Banerjee, N. Michalopoulos, N. Williams, T. Davidson, S. El Seik, N. Mcdermott, M. Tran-Dang, S. Davison, M. Keshtgar Royal Free London NHS Foundation Trust Introduction: One step nucleic acid amplification (OSNA) is a recently

developed molecular diagnostic assay to detect lymph node metastases. Aim of this study was to assess OSNA for intra-operative detection of sentinel node

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metastases in breast cancer with use of standard histopathology as the ‘‘gold standard’’. Discordant cases were reviewed and further investigated to assess their impact on patients’ management. Methods: 170 breast cancer patients with clinically and ultrasonographically negative axilla underwent axillary staging with sentinel node biopsy. 270 sentinel lymph nodes were intra-operatively evaluated by OSNA and subsequently with standard histopathology undertaken on alternate slices of the excised nodes. Axillary node clearance was performed if the sentinel node was positive for OSNA or histopathology. The time taken for an OSNA result was recorded. Results: Sensitivity and specificity of OSNA were calculated at 95.5% and 96% respectively. Concordance between OSNA and Histopathology was 95.5% with positive predictive value and negative predictive value of OSNA 80% and 99% respectively. Discordant nodes were identified in 12 patients. In 7 patients axillary node clearance was performed on the basis of the OSNA result alone. 2 patients underwent delayed axillary node clearance when histopathology showed metastases after a negative OSNA result. Turn- around time for an OSNA result for 1 node was 44 minutes (range 37–50) and 2 nodes 60 minutes (range 50–79). Conclusion: OSNA is a reliable, highly accurate standardised method for the intra-operative evaluation of axillary lymph node metastasis with very few patients requiring delayed axillary node clearance in our study. Take-home message: OSNA is a reliable, highly accurate standardised method for the intraoperative evaluation of axillary lymph node metastasis with very few patients requiring delayed axillary node clearance.

O19 Response of colorectal cancer cells to different MEK inhibitors ´ ´ V. Lopez-D avila, H. Welch, M. Loizidou Division of Surgery and Interventional Sciences, University College London

Introduction: Myeloid cells aid the progression of various cancers. We

identified a murine myeloid population recruited to the liver during the development of colorectal hepatic metastasis. Inhibition of myeloid recruitment through inhibition of the tumour-derived chemokine CCL2 delayed murine metastases and thus implicated a potential therapeutic target for patients with metastatic colorectal cancer. Methods: Murine hepatic metastases were induced by intrasplenic injection of MC38 colon cancer cells. Myeloid populations were identified by flow cytometry. Tumour-derived chemokines were detected in cell-conditioned medium by protein array. MC38-derived CCL2 was inhibited using shRNA. Serum CCL2 expression was quantified by ELISA in 130 colon cancer patients and metastatic colon cancer tissues were analysed immunohistochemically. Results: Cells co-expressing the myeloid markers Gr1 and CD11b and the chemokine receptor CCR2 (CD11b+/CCR2+) increased 6-fold in mouse liver bearing hepatic metastases compared with controls. MC38 cells expressed CCL2 and murine serum CCL2 concentration correlated with tumour burden and hepatic CD11b+/CCR2+ count suggesting a role for CCL2 in their recruitment. Consistent with this, inhibition of MC38-derived CCL2 reduced hepatic CD11b+/CCR2+ recruitment, delaying metastatic development. Serum CCL2 was elevated in patients with colon cancer compared to healthy controls. Furthermore, CCR2 and CD11b co-localised within human hepatic metastases indicating the presence of a myeloid population similar to that seen in metastasis-bearing mice. Conclusions: Recruitment of CD11b+/CCR2+ myeloid cells through the tumour-derived chemokine CCL2 aids the development of murine hepatic metastases. The development of therapeutics aimed at inhibiting myeloid cell trafficking may improve operability and survival for patients with metastatic colorectal cancer. Take-home message: A specific sub-set of myeloid cells are recruited to colon cancer metastases via the action of the tumour-derived chemokine CCL2. Inhibition of this process via manipulation of the chemokine pathway delays the development of hepatic metastasis.

Introduction: The MAP kinase pathway is essential in most cell types and its

aberrant activation in many cancers leads to enhanced proliferation and survival, among other effects. New chemotherapeutics directed against the kinase MEK successfully interrupt its signalling cascade; however, their efficacies vary among cancer subtypes. Methods: Two colorectal cancer cell lines, HT29 and HCT116, bearing mutations in BRAF and KRAS respectively (upstream of MEK), were treated with the MEK inhibitors AZD6244 (currently in clinical trials), PD98059 and U0126. Their effects on cell proliferation were measured by metabolic activity (MTT assay) and by total DNA quantification. Findings were complimented by western blotting of phosphorylated ERK (pERK) after treatment with the inhibitors and activation of the pathway with EGF. Quantitative RT-PCR was performed to validate MEK as a target. Results: AZD6244 (1nM-10µM) and PD98059 (10-100µM) showed a consistent dose-dependent inhibition of proliferation in both cell lines; [AZD6244: p < 0.001 at 100nM (HT29) and at 1µM (HCT116), PD98059: p < 0.05 at 100µM (HCT116) and p < 0.01 at 50nM (HT29)]. Conversely, U0126 (10nM-1µM) induced proliferation in HT29 (p < 0.001 at 50nM) and inhibited proliferation in HCT116 (p < 0.001 at 1µM). Increasing concentrations of AZD6244 reduced the levels of pERK, demonstrating that proliferation inhibition is due to impairment of MEK activity. There was also a positive correlation between increased proliferation and pERK in U0126 treated HT29 cells. Conclusion: AZD6244 may be a promising therapeutic molecule against certain colorectal cancers, while the contradictory effect of U0126 on proliferation is consistent with reports on various anti-cancer drugs in vitro. Take-home message: AZD6244 may be a promising therapeutic molecule for certain colorectal cancers.

O20 RSM MIA Prize Winner Myeloid cells are recruited by liver metastases and aid their development A. N. Gordon-Weeks, L. Zhao, S. Y. Lim, Y. Cao, J. Beech, D. Allen, S. Smart, R. J. Muschel Gray Institute for Radiation Oncology and Biology, University of Oxford


O21 Methylation of the notch pathway in patients at higher risk of colorectal cancer and effects of supplentation with resistant starch in a randomised controlled trial I. J. D McCallum1,2 , S. B. Kelly1 , M. Bradburn1 , N. Willis2 , L. Xie2 , J. C. Mathers2 1 North Tyneside Hospital, North Shields, UK, 2 Human Nutrition Research Centre,

Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, NE4 5PL, UK Introduction: Colorectal cancer (CRC) arises from genetic defects in stem

cells. Notch signalling plays a key role in stem cell replication. NOTCHrelated genes are overexpressed in CRC. The mechanism for this is not known but could include epigenetic activation of NOTCH oncogenes via promoter hypomethylation. Methylation can be modulated by environmental stimuli including dietary factors such as butyrate, produced by bacterial fermentation of non-digestible carbohydrates in the colon. Butyrate exerts potent anti-oncogenic effects in the colorectal mucosa. Methods: Participants were recruited at endoscopy and included those at normal risk of CRC (n = 75), or higher risk of CRC because of previous adenomatous polyps (n = 28) or ulcerative colitis (n = 12). Participants provided 9 rectal biopsies. Normal risk participants were randomised to resistant starch (Hi-maize260) or polydextrose in a 2x2 factorial placebo controlled trial for 50 days. Methylation of several CpG sites in the promoters of JAG1 (NOTCH pathway ligand) and RBP-J (NOTCH intracellular activator) was quantified using pyrosequencing. Results: For JAG1 there was trend towards lower methylation at all CpG sites in those at higher CRC risk. Methylation at RBP-J CpG 11 was lower in polyp patients than in controls (18.0(1.5) vs. 23.6% (0.8), p = 0.011). At JAG1 CpG 4, methylation increased following polydextrose supplementation compared to placebo (3.1(0.4) vs. 1.7%(0.4), p = 0.009). A similar, but non-significant, trend was observed at other CpG sites for JAG1.

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Conclusions: DNA methylation of NOTCH signalling genes is altered in

Methods: A total of 794 patients from 27 UK centres were randomised to

macroscopically normal colorectal mucosa of patients at higher CRC risk. The observed changes in JAG1 methylation after polydextrose supplementation are consistent with a protective effect against carcinogenesis. Take-home message: Notch signalling activation is a key process in colorectal carcinogenesis for which no mechanism has yet been established. This study suggests that methylation alterations of the genome may result in epigentic activation of the Notch pathway and that dietary intervention may modulate this change.

laparoscopic or open surgery in a 2:1 ratio between 1996 and 2002. Longterm follow-up data involving intention-to-treat and actual treatment groups was analysed to determine differences in survival outcomes and recurrences. Survival and recurrence data were compared using Kaplan-Meier and cumulative incidence function curves respectively, and tested using log-rank and Wilcoxon rank-sum tests. Results: Median follow-up of all patients was 62.9 (IQR: 22.9-92.8) months. For all patients median OS was 85.1 (95% CI 72.7-105.7) and 73.6 (95% CI 64.389.5) months, whereas DFS was 94.8 (95% CI 74.2-108.7) and 70.6 (95% CI 55.0-85.5) months for colon and rectal cancer respectively, with no difference by randomised procedure for either OS (p = 0.78) or DFS (P = 0.59). Colon cancer patients experienced significantly worse OS (P = 0.0005) and DFS (P = 0.0068) following conversion. No significant difference in recurrences were observed by randomised procedure; however at 10 years right-sided local recurrence was increased (14.7%) compared to left-sided (5.2%), P = 0.019. Rectal cancer patients experienced significantly improved early survival with laparoscopic surgery, Wilcoxon P = 0.0071. Conclusions: Long-term results continue to support the use of laparoscopic surgery for colon and rectal cancer. Trends in local recurrence warrant further investigation. Take-home message: Laparoscopic surgery is a safe alternative to conventional open surgery in the treatment of both colon and rectal cancer in suitable patients.

O22 Progressive alterations in CD4+ T cell phenotypes in breast cancer patients following chemotherapy R. Verma1,3 , N. L. Smalle2 , R. E. McCurtin2 , K. Horgan1 , T. A. Hughes3 , C. R. D. Carter2 1 Department of Surgery, Leeds General Infirmary, Leeds, UK, 2 Department of

Immunology and Transplant Immunology, St James’s University Hospital, Leeds, UK, 3 Leeds Institute of Molecular Medicine, University of Leeds, Leeds, UK

Introduction: Initial immune toxicities of chemotherapy have been reported

but longer-term effects are less clear. Our aims were to study the time-course and determinants of changes in T lymphocytes during and after breast cancer chemotherapy, and to define characteristics of repopulating cells. Methods: Ethical approval was obtained. Peripheral blood was collected from 88 patients during/after primary breast cancer treatment. Lymphocyte numbers/phenotypes were assessed by flow-cytometry. Results: Chemotherapy resulted in significant reductions in numbers of circulating CD4+ (median 39.2% of pre-chemotherapy levels, p < 0.001) and CD8+ T cells (51.6%, p < 0.001). At 9 months post-chemotherapy there was almost complete recovery of CD8+ cells (94.0% of pre-chemotherapy level), but only partial recovery in CD4+ cells (54.8%, p = 0.013). The CD4+ T cells present during recovery also differed in phenotype from pre-chemotherapy and showed little sign of normalizing. Indeed, phenotypes continued to diverge progressively from pre-chemotherapy levels. CD45RO+ memory CD4+ T cells progressively expanded from 62.8% of the CD4+ compartment prechemotherapy to 67.8% at 2 weeks, and 73.8% at 9 months post-chemotherapy (p < 0.006). Similarly, at the same time-points na¨ıve CD4+RA+CD62L+ cells decreased from 46.6% to 34.0% and 33.7% (p < 0.03). CD4+ CD45R0CD31+ recent thymic emigrants also decreased from 23.0% to 18.3% and 13.7% (p < 0.001), Finally, CD25hiFoxP3+ regulatory cells expanded from 3.0% to 3.4% and 5.26% (p < 0.001), increases that were particularly prevalent in patients presenting with larger tumours (p = 0.012) or undergoing herceptin therapy (p = 0.028). Conclusion: T cell levels and phenotypes remain altered even 9 months after chemotherapy, hinting at potential long-term immune defects. Take-home message: T cell levels and phenotypes remain altered even 9 months after chemotherapy, hinting at potential long-term immune defects.

O23 Long term follow-up of the mrc conventional versus laparoscopically assisted resection in colorectal cancer trial B. L. Green1 , H. C. Marshall1 , F. Collinson1 , D. G. Jayne2 , J. M. Brown1 1 Clinical Trials Research Unit, University of Leeds, Leeds, UK, 2 Section of

Translational Anaesthesia and Surgery, Leeds Institute of Molecular Medicine, St James’s University Hospital, Leeds, UK Introduction: Laparoscopic resection is widely used in the management of

colorectal cancer; however there is limited data regarding long-term outcomes, particularly regarding rectal cancer. This study presents the long-term follow up of the MRC-CLASICC trial of conventional versus laparoscopic surgery in the treatment of colorectal cancer.


O24 RSM MIA prize runner-up Global analysis of the SRC-1 and HOXC-11 transcriptomes identifies a novel role for SRC-1 and HOXC-11 in suppressing luminal a markers in breast cancer J. C. Bolger1 , C. A. Walsh1 , D. P. McCartan1 , A. Cahalin1 , Y. Hao2 , J. Xu2 , P. O’Gaora2 , A. D. Hill1 , L. S. Young1 1 Endocrine Oncology Research, Royal College of Surgeons in Ireland, Dublin 2, 2 School

of Medicine, Conway Institute, University College Dublin. Introduction: Recurrent breast cancer may offer a different phenotype than

the primary tumour. Cellular plasticity may drive a more aggressive phenotype in response to environmental stimuli. We describe crosstalk between steroid (SRC-1) and developmental (HOXC-11) pathways, identifying novel common targets PAWR and CD24 and examine their influence at cellular and patient level. Methods: Common SRC-1 and HOXC-11 targets were identified following ChIPseq analysis of endocrine-resistant breast cancer cell lines. Regulation was confirmed by RT-PCR, Western blotting and flow cytometry using siRNA and in an SRC-1 knockout mouse. Gene methylation status was confirmed using methylation-specific arrays and methylation-specific DNA sequencing. A TMA comprising 560 patients was stained for SRC-1, PAWR and CD24 as were three patient samples of primary and recurrent tissue. Results: Bioinformatic analysis identified 92 common targets. Luminal A markers PAWR and CD24, were down-regulated by SRC-1/HOXC11. PAWR/CD24 down-regulation was confirmed in cell lines. Methylationspecific arrays showed significant de-methylation of PAWR promoter with HOXC11 knockdown. CD24 promoter was de-methylated following SRC-1 knockdown. In our TMA, PAWR and CD24 associated with good diseasefree survival (p < 0.01 and 0.001), luminal A status (p < 0.001) and inversely with SRC-1 (p < 0.001). In endocrine-treated recurrences, primary tumours were luminal A (PAWR+, CD24+, SRC-1-). In recurrent tissue SRC-1 was up-regulated, while PAWR and CD24 were suppressed. Conclusions: We describe a novel role for SRC-1 as a co-repressor. PAWR and CD24 may be suppressed by SRC-1 and HOXC11 via methylation. In endocrine-treated patients who recur, SRC-1 may drive an aggressive phenotype and suppress luminal A markers. Take-home message: This work identifies a novel mechanism for SRC-1 to operate as a co-repressor and uncovers novel therapeutic potential.

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(p < 0.05). There were no differences in VSS scores at other time-points; at 18 and 24 months we predict this was due to loss of follow-up. Conclusions: These data suggest that propranolol improves scar appearance up to 12 months post-injury. Planimetric data is needed to provide an objective measure of this improvement. Enrolment of more patients beyond 18 months is necessary to determine whether the reduction in scarring by propranolol is sustainable. Take-home message: Propranolol is not only beneficial in ameliorting the hypermetabolic response to burns but may also improve cosmetic outcomes of burns.

MEDICAL STUDENT PRIZE

O25 Elevated expression of miR-106 and miR-202 in breast cancer M. McLoughlin, C. L. Glynn, P. S. Waters, S. Khan, R. M. Dwyer, M. J. Kerin Discipline of Surgery, School of Medicine, National University of Ireland Galway, Galway, Ireland Introduction: MicroRNAs(miRNAs) are small non-coding RNA molecules,

known to regulate gene expression at the post-transcriptional level. A recent study in this laboratory determined that circulating miR-106 and miR-202 were dysregulated in the breast cancer setting. The aim of this study was to investigate miR-106 and miR-202 expression in breast tumour compared to healthy tissue, to determine whether circulating levels reflected changes in the tumour microenvironment. Methods: Tissue explants were harvested in theatre from breast cancer patients(n = 20), with normal tissue(n = 20) harvested at reduction mammoplasty. Each sample underwent Trizol homogenisation, followed by extraction using the RNeasy isolation kit (Qiagen), and reverse transcription. Samples were then amplified by RQ-PCR targeting miR-106, miR-202 and the endogenous controls miR-16 and let-7A, with relative levels of each microRNA determined in malignant compared to normal tissue. Results: Mir-106 and mir-202 expression was detected in all tumour(n = 20) and normal(n = 20) tissues. Expression of miR-202 was found to be significantly elevated in tumour (Log10 Relative Quantity (RQ) ±SEM; 1.58 ± 0.14) compared to normal tissues (Log10 RQ, 0.92 ± 0.112, p < 0.005). Although to a lesser extent, expression of mir-106 was also found to be significantly upregulated in tumour tissues (Log10 RQ 1.56 ± 0.184) compared to healthy controls (Log10 RQ 1.09 ± 0.13, p < 0.05). Conclusion: This study revealed dysregulated expression of both mir-106 and mir-202 in breast cancer tissue, mirroring similar findings in the circulation. This suggests a role for these miRNAs in disease progression, and highlights their potential as both circulating biomarkers of disease, and potential therapeutic targets. Take-home message: miR-106 and miR-202, two microRNAs recently identified to be dysregulated in a breast cancer setting, have been proved to be dysregulated in human breast cancer tissue. This suggests a role for these miRNAs in disease progression and highlights their potential as biomarkers and therapeutic targets.

O26 The effect of propranolol on post-burn scar appearance: A randomised, controlled trial N. T. Mabvuure1 , A. El-ayadi2 , D. N. Herndon2 , H. Hawkins2 , C. C. Finnerty2 1 Brighton and Sussex Medical School, Brighton, UK, 2 Shriners Hospital for Children

Galveston, Galveston, TX, USA Introduction: Propranolol attenuates post-burn hypermetabolism and reverses

muscle-protein catabolism. In a small study (n < 40), propranolol reduced the appearance of scar severity. This randomised, controlled trial aimed to study the effects of propranolol on post-burn scars in a larger group of patients. Methods: children were randomised to receive propranolol (n = 90) or a control (n = 89) for up to 12 months post-injury. Vancouver Scar Scale (VSS) assessments were carried out on leg scars at 6, 9, 12, 18 and 24 months follow-up by one assessor blinded to treatments received. Statistical analysis was performed on an intention-to-treat-basis using t-tests and the Wilcoxin 2-sample rank sum test. Results: Participants had a mean age of 7.01 with burns covering a mean of 56.6% of their total burn surface area (TBSA). The groups were similar in demographics, TBSA and mechanism of burn. At 9 and 12 months followup, the propranolol group had significantly lower VSS scores than controls


O27 WISP-2 regulates coloretcal cancer cell invasion and motility K. A. Frewer, A. J. Sanders, R. Hargest, W. G. Jiang Metastasis and Angiogenesis Research Group, Institute of Cancer and Genetics, Cardiff University School of Medicine, Heath Park, Cardiff, UK Introduction: WISP-2 may act as a tumour suppressor in colorectal cancer

(CRC). Disruption of WISP-2 signalling in MCF-7 breast cancer cells results in a significant increase in cell migration and invasion. WISP-2 may play an important role in CRC metastasis. We investigated the effect of WISP-2 knockout on Caco2 cell invasion together with potential mechanisms of action. Methods: WISP-2 knockout expression was targeted in Caco2 cells using a ribozyme transgene system. The impact of WISP-2 knockout on motility and invasion was examined in vitro both in the presence and absence of wnt inhibitors (FH535 and IWP-2). Quantative PCR was conducted to measure MMP expression in control and knockout cells. Results WISP-2 knockout resulted in a significant increase in Caco2 cell invasion (WT 7+/−3.58 vs WISP-2 KO 40+/−19.78 p = 0.014 and pEF6 8 +/− 27 vs WISP-2 KO 40 +/−19.78 p = 0.016) and motility (WT 0.096 +/−0.015 vs WISP-2 KO 0.15 +/−0.024 p < 0.001 and pEF6 0.073 +/−0.0054 vs WISP-2 KO 0.15 +/−0.024 p = 0.01). Results indicated upregulation of MMP-2, MMP-9 (both not significant p > 0.05) and MMP-7 (p = 0.025) in WISP-2 KO cells compared to controls. Results showed inhibiting wnt signalling had no effect on WISP-2 KO cell motility (FH535 p = 0.573) (IWP-2 p = 0.547) There was a significant decrease in WISP-2 KO cell invasion (FH535 p = 0.025) and (IWP-2 p = 0.017) Conclusions: WISP-2 knockout significantly increased Caco2 cell invasion and motility. Upregulation of MMP 2, 7 and 9 may indicate WISP-2 regulates invasion and motility through MMPs. Regulation of invasion by WISP-2 may involve the wnt- signalling pathway. Take-home message: WISP-2 may regulate colorectal cancer cell invasion through the wnt signalling pathway and upregulation of MMP-2, MMP-9 and MMP-7.

O28 Factor XIII Val34Leu polymorphism and diabetes in abdominal aortic aneurysms H. L. Evans1,2 , K. J. Griffin1,3 , F. Macrae1 , M. A. Bailey1,3 , S. Sohrabi1 , D. J. A. Scott1,3 , R. A. S. Ariens1 1 DCDR, LIGHT institute, Leeds, 2 University of Leeds, Leeds, 3 Leeds Vascular

Institute, Leeds General Infirmary, Leeds Introduction: Despite the association with other cardiovascular disorders,

DM is thought to be protective against the development and growth of AAA. The presence of the Val34Leu polymorphism in clotting Factor XIII (FXIII) is known to affect fibrin structure. Whilst FXIII-Val34Leu is protective against cardiovascular disease, the presence of insulin resistance negates this. The role of FXIII-Val34Leu in AAA patients with or without DM is unknown. Methods: DNA was extracted from 438 AAA patients and 343 controls. Samples were analysed by real-time-PCR for FXIII-Val34Leu. DM-status was determined by patient history, fasting glucose and glucose tolerance testing.

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SARS abstracts

Correlation between genotype, AAA and DM status was analysed by Chi-squared and Student-t tests; survival was analysed by Kaplan-Meier. Results: Mean crude survival for AAA patients with >1 Leu allele was 6.24(CI 5.75–6.73) compared to 7.01(CI 6.62–7.40) years for Val/Val, (p = 0.021). This difference was not observed in the control group, 9.34(CI 9.13–9.61) and 9.26(CI 9.13–9.73) years respectively (p = 0.6). There was no difference between AAA patients and controls regarding Val34Leu genotype distribution, however there were more AAA patients with DM and >1 Leu allele (55.6%) compared with AAA patients without DM (40.3%), p = 0.023. Conclusion: Our data show that FXIII-Leu34 is associated with increased overall mortality in AAA. Additionally, FXIII-Leu34 was more prevalent in those patients with both DM and AAA. These data suggest that 1) FXIIILeu34 may increase the risk of rupture or risk of peri-repair complications in AAA patients, and 2) FXIII-Leu34 may negate the protective effect of DM in AAA. Take-home message: FXIII-Leu34 may increase the risk of rupture or risk of peri-repair complications in AAA patients, and FXIII-Leu34 may negate the protective effect of DM in AAA.

O29 Medical Student Prize Winner Interleukin-24 and lymphangiogenesis of human breast cancer N. C. Frewer, L. Ye, P.-H. Sun, K. Ji, R. Hargest, W. G. Jiang Metastasis and Angiogenesis Research Group, Institute of Cancer and Genetics (Section of Surgery), Cardiff University School of Medicine, Heath Park, Cardiff

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progressive and irreversible reduction of airway function termed Bronchiolitis Obliterans Syndrome. The aim of this work was to analyse the expression of a panel of genes implicated in chronic allograft rejection by microarray. Methods: Lung epithelial cell line (A549), patient derived primary bronchial epithelial cells (PBECs) and frozen post transplantation bronchial alveolar lavage (BAL) samples were used. Immunofluorescence on H2O2 treated A549 cells was performed to identify mesenchymal markers. A549 and PBECs were also treated with IFN-y, RNA extracted and cDNA synthesis performed. Changes in gene expression were calculated using the integrated web based software. Results: Oxidative stress of A549 cells induced epithelial to mesenchymal transition (EMT) and this was evidenced by significant reduction (p < 0.05) of epithelial cell surface proteins, Cytokeratin 7 and E-cadherin, and the increase (p < 0.05) of mesenchymal extracellular proteins, S100A4 and Vimentin, with treatment time. IFN-y stimulated, A549 and PBECs had significant increase in expression of chemokines (CXCL6 and CCL2), cytokines (IL6, IL8 and IL17A) and BMP7 an EMT mediator. Furthermore, patient BAL samples had significant upregulation (p < 0.01) of Heparanase, Versican and IL8 which are documented to be associated with chronic allograft rejection. Conclusion: These results suggest that A549 cells are a satisfactory model for Chronic allograft lung research and the feasibility of using BAL samples for microarray analysis. Thus further research using Biobank patient BAL samples could be used to validate these biomarkers of chronic lung rejection. Take-home message: Post transplantation frozen bronchoalveolar lavage samples can be used for microarray analysis, and the up regulation of genes and extracellular matrix protein, implicated with chronic lung allograft rejection has been shown using the A549 cell line.

Introduction: Lymphangiogenesis may be important in cancer metastasis.

Vascular endothelial growth factors C and D (VEGF-C and VEGF-D) and lymphangiogenic markers (podoplanin, Prox-1 and LYVE-1) play an essential role. Interleukin-24 (IL-24) (a cytokine with potent anti tumour activity) functions through association with its receptor (IL-22R). Methods: Breast cancer tissue samples (n = 127) were collected following informed consent. Transcript levels of IL-24, IL-22R and lymphangiogenic factors and markers were determined using real time PCR. In vitro assays assessed the influence of IL-24 on endothelial cell growth and microtubule formation. The effect of IL-24 on mRNA expression of lymphangiogenic factors and markers was determined using QPCR and conventional PCR with semi quantitative analysis. Results: Analysis of malignant breast tissue samples revealed a correlation between increased expression of podoplanin and significantly reduced levels of IL-24 (p < 0.01) and IL-22R (p < 0.05). Increased expression of LYVE-1 was associated with significantly reduced expression of IL-24 (p < 0.05). In vitro functional assays were performed. The average perimeter lengths of microtubules formed by endothelial cells treated with IL-24 (25ng/ml) was significantly reduced compared to the control (p < 0.001). IL-24 (250ng/ml) suppressed microtubule formation to a further lower degree. Growth of endothelial cells was significantly reduced when exposed to a high concentration of IL-24 (250ng/ml) compared to the control (p < 0.05). Treatment of HECV cells with IL-24 resulted in significantly reduced mRNA expression of VEGF-C (p < 0.05) and VEGF-D (p < 0.001). Conclusions: IL-24 may play a role in suppressing breast tumour lymphangiogenesis thereby reducing the likelihood of cancer metastasis via the lymphatic route. Take-home message: Decreased expression of IL-24 in breast cancer tissue may be associated with increased potential for tumour lymphangiogenesis and cancer metastasis via the lymphatic route.

O30 Identification of biomolecular marker of chronic lung allograft rejection I. Atugba, C. Ward, S. Ali Newcastle University, Institute of Cellular Medicine Introduction: Transplantation is the only potentially curative treatment for

O31 Promoter methylation of zinc transporter genes in the ageing human bowel E. Kilcourse, J. McKay, N. Willis, J. C. Mathers Institute for Ageing and Health, Newcastle University Introduction: The ageing process is accompanied with epigenetic modification

that may influence health; one such modification is gene promoter hypermethylation. Hypermethylation can initiate transcriptional silencing and loss of gene expression. Mechanisms that control gene expression are central to zinc homeostasis. Zinc deficiency contributes to frailty, reduced immune response and age-related diseases in the elderly. Yet the methylation of Zinc transporters (ZNTs) is largely unknown. Aims: 1) Quantify methylation with age in the promoters ZNT3, ZNT5 and ZNT6 in colorectal mucosa; 2) Compare methylation of these ZNTs in normal versus colorectal cancer (CRC) samples. Methods: DNA extracted from normal colorectal mucosa and CRC samples. Samples bisulphite modified. Selected CpG-dense regions of ZNT3, ZNT5 and ZNT6 promoters were amplified by PCR and analysed by pyrosequencing to quantify methylation. Results: ZNT3 methylation increased with age (p = 0.006). ZNT5 methylation decreased with age (p = 0.06). ZNT6 was unmethylated. Methylation of ZNT3 was significantly increased in CRC compared to normal controls (p = 0.011). Conclusion: ZNT3 is not normally expressed in the colon; increasing ZNT3 methylation with age may: 1) alter transporter expression, 2) be a consequence of localised chromatin remodelling. Alternatively, methylation changes may not be functional, but indicate a plethora of age (or disease) associated epigenetic changes. Given the association between ZNT3 methylation and CRC, hypermethylation at this locus may be a biomarker of unhealthy ageing of the colon. Decreased ZNT5 methylation with age may increase transporter expression in ageing colon. Future work, quantify gene expression of ZNT3 and ZNT5 in the colon using mRNA and proteomic techniques. Take-home message: Zinc is an important micronutrient in humans, this study observed significant methylation changes of zinc transporter genes ZNT3 and ZNT5 in the human colon. These methylation changes may be a biomarker of unhealthy ageing of the human colon and may have consequences for ageing.

end-stage respiratory disease. Chronic allograft rejection however, results in the


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Conclusion: This study revealed disruption in SMC phenotype and function in

O32 Effective targeting of MEK (MAP kinase, kinase) in breast cancer cells G. Gan, N. Roberts, V. Lopez-Davila, M. Loizidou, H. Welch Division of Surgery and Interventional Science, UCL Medical School Royal Free Campus Introduction: The heterogeneous nature of breast cancer presents a

considerable challenge to management and therapy. The MAP Kinase pathway is a focal point for cross-talk between ER and HER2 signalling pathways; it is implicated in both inherent and acquired resistance to endocrine therapies and contributes to resistance of HER2-directed therapies. The aim of this study was to investigate the efficacy of different inhibitors of one of the pathway kinases (MEK; MAP Kinase, Kinase) in breast cancer cells. Methods: A panel of breast cancer cells (including MCF-7, SkBr3 and ZR75-1 cells) were examined for their response to the MEK inhibitors U0126 and PD98059. Proliferation/inhibition was measured by metabolic assay (MTT). Activation/inhibition of the MAPK pathway was assayed by ±phosphorylation of ERK1/2 (MEK substrates) by Immunoblotting. Expression levels were quantified by real-time RT-PCR. Results: EGF-stimulated phosphorylation of ERK1/2 occurred within 2min in SkBr3 cells and was sustained for over 90min, whereas phosphorylation of ERK1/2 took 5min in MCF-7 cells and appeared transient. The inhibitor U0126 (a) effectively blocked ERK1/2 phosphorylation in MCF-7, SkBr3 and ZR-75-1 cells and (b), inhibited cell proliferation. In contrast (a) PD98059 failed to block EGF-stimulated phosphorylation of ERK1/2 in these cells and (b) induced proliferation in five of six cell lines (22-100% above controls at 10uM; p < 0.05). Conclusions: MEK is a potential therapeutic target for certain breast carcinomas, including HER2-positive tumours. However, further work is required to establish (i) the most effective inhibitor and (ii) which other genetic/proteome cancer profiles would benefit most from this therapy. Take-home message: MEK inhibitors have considerable potential for: (a) use as an adjuvant therapy; (b) elucidating the complexity of signal transduction pathways; and (c) the mechanisms of resistance in breast cancer cells.

O33 Utilising a bioreactor to evaluate smooth muscle cell phenotype and function in protease treated porcine artery model of AAA disease G. S. Mudhar1 , K. Riches2 , P. Walker3 , S. Sohrabi4 , D. J. A. Scott2,4 , K. E. Porter2 1 School of Medicine, University of Leeds, 2 Division of Cardiovascular Medicine, Leeds Institute for Genetics, Health and Therapeutics (LIGHT), 3 School of Engineering, University of Leeds, 4 Department of Vascular Surgery, Leeds General Infirmary

Introduction: Abdominal aortic aneurysms (AAA) are a progressive silent

disease with a high mortality. Despite the key role of vascular smooth muscle cells (SMC) in arterial function, little is known of their involvement in the progression of AAA disease. The aim of this study was to simulate extra-cellular matrix (ECM) degradation associated with aneurysm formation in porcine carotid arteries in a novel bioreactor and to understand structural and functional changes in SMC cultured from the recovered vessels. Methods: Porcine arteries were pretreated with collagenase and/or elastase before culturing under flow in a bioreactor for 12 days. SMC were subsequently explanted, cultured and characterised (immunocytochemistry, measurement of spread cell area) and assessed functionally at the level of proliferation (cell-counting) and matrix-metalloproteinase secretion (gelatin zymography). Results: All cells co-expressed alpha-smooth muscle actin and smooth muscle myosin heavy chain, confirming SMC phenotype. Viable SMC were obtained from all vessels, but those receiving combined collagenase/elastase pretreatment displayed a prominent ‘‘rhomboid’’ morphology, increased area (p < 0.01, oneway ANOVA, n = 50), impaired proliferation (2.5-fold reduction) (p < 0.05, one-way ANOVA, n = 3) and ∼60% reduction in matrix metalloproteinase-2 secretion (n = 3), compared with SMC from either collagenase alone, elastase alone or vehicle control vessels.


protease-treated porcine vessels comparable with those observed in ‘‘end-stage’’ human AAA-SMC. The bioreactor is thus a useful model to induce aspects of AAA development and suggests that targeting SMC directly may be a potential therapeutic strategy in AAA disease. Take-home message: SMC have been cultured from vessels exposed from the bioreactor which are similar to what are seen in patients with AAA. The bioreactor is therefore a useful model to understand AAA development further as well as possible therapies.

O34 Radiofrequency tissue fusion for small bowel sealing: A study of seal quality using mechanical testing and imaging N. Hadjievangelou1 , S. Arya1 , L. Su1 , H. Kudo2 , R. D. Goldin2 , A. W. Darzi1 , D. S. Elson1 , G. B. Hanna1 1 Division of Surgery, Department of Surgery and Cancer, Imperial College London, St Mary’s Hospital, South Wharf Road, London, 2 Centre for Pathology, Department

of Cellular Pathology, St Mary’s Hospital, South Wharf Road, London Introduction: Bowel anastomosis has traditionally been accomplished using

sutures and staples. Bipolar radiofrequency (RF) induced tissue fusion, an energy-based method of tissue approximation, is believed to have the potential for forming intestinal seals and anastomoses thereby reducing the morbidity and mortality associated with current techniques. This study assessed the effects of RF energy and varying compressive pressures when creating intestinal seals in ex-vivo porcine small bowel. Methods: 299 mucosa-to-mucosa fusions were formed on ex-vivo porcine small bowel segments using a closed-loop feedback controlled RF generator and a prototype anastomosis device. Compressive pressures were incrementally increased at 0.05MPa intervals from 0.00-0.49MPa and RF energy applied. Bowel seal strength was assessed using burst pressure and tensile strength testing. Morphological changes were examined through light microscopy and TEM (transmission electron microscopy). Results: An optimal applied compressive pressure range was detected between 0.10-0.25MPa. A step change in strength was observed on applying pressures greater than 0.10MPa. Peak mean bursting pressure was 27.56 mmHg(0.15 MPa), whilst peak mean breaking strength was 1.22 N (0.20 MPa). Light microscopy demonstrated incomplete seals on applying pressures less than 0.10MPa but was ineffective in distinguishing between pressure levels once tissues were sealed. Non uniform collagen damage was observed in the sealed area using TEM, which has not previously been described in RF fused tissue and may have implications for in vivo healing. Conclusions: This study confirms that both bipolar RF energy and optimal compressive pressures are needed to form intestinal seals. The observations from mechanical testing and imaging suggest that RF technology can be effective in bowel sealing. Take-home message: RF induced bowel sealing is feasible and has the potential to become an anastomotic tool.

O35 Relationship between circulating miRNAs and breast cancer epithelial subtype M. F. Duignan, C. Brougham, P. S. Waters, R. M. Dwyer, Michael J. Kerin Discipline of Surgery, School of Medicine, National University of Ireland, Galway Introduction: MicroRNAs(miRNAs) are non-coding RNAs that inhibit gene

expression post-transcriptionally. They play a distinct role in breast cancer, and in tumour tissue, have been linked with epithelial subtype of the disease. The aim of this study was to determine the circulating level of two novel miRNAs in breast cancer patients and healthy controls, and investigate any relationship with tumour epithelial subtype.

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Methods: miRNAs were extracted from whole blood harvested from 46 breast

cancer patients and 33 healthy controls. Samples were reverse transcribed and RQ- PCR performed targeting miR-106a and a novel miRNA, miR-A. Endogenous controls miR-16 and U6 were also analysed, and the relative quantity of each miRNA determined. Results: miR-106a was detected in the circulation of 46 breast cancer patients and 33 healthy controls, with lower levels detected in breast cancer patients (p = 0.052). When divided on the basis of epithelial subtype, patients with basal type breast cancer(n = 22) had significantly lower levels of circulating miR-106a than those with other subtypes of the disease, or healthy controls (p < 0.001). In contrast, a novel miRNA, miR-A, was found to be significantly elevated in breast cancer patients compared to healthy controls, regardless of epithelial subtype (p < 0.005). Conclusions: Understanding the mode of action of miR-106a may provide valuable insight into the molecular biology of basal subtype breast cancer, which currently presents significant challenges in the clinical setting. This is the first study to report circulating miR-A in breast cancer patients, with initial data strongly supporting a potential role as a biomarker of disease. Take-home message: It is vital to understand the precise role that miR-106a plays in breast cancer molecular biology. This is to be ascertained if it may be used clinically as a biomarker for the early diagnosis of the disease.

ORAL PRESENTATIONS 1A BREAST SURGERY

O36 Importance of monitoring bone health in breast cancer O. Choudhry2 , L. Olson1 , Z. Saad1 , S. Chatterjee1 1 Salford Royal Foundation Trust, 2 University of Manchester Medical School

Introduction: Aromatase inhibitors used in the management of breast cancer

are associated with premature bone mineral density loss due to reduced circulating oestrogen, which in turn leaves patients susceptible to fragility fractures. The aims of this retrospective study are to assess whether patients within this trust are being managed appropriately in accordance with guidelines regarding bone health; whether these practices are cost – effective and if mammographic breast tissue density has a clinical use in predicting osteoporosis development. Method: Retrospective analyses and comparisons of breast cancer and bone health management, DEXA scans and BIRADS scores were performed using 248 patient records between 2008 and 2011. Results: 84% of patients were appropriately managed regarding bone health prior to DEXA scanning. Following DEXA scanning, 59% of patients were found to be osteopenic and 13% osteoporotic. Following identification, 5% of osteopenic patients and 19% of osteoporotic patients were not on appropriate treatment according to guidelines. A fragility fracture rate of 2.5% was observed, with 50% of these fractures occurring amongst osteopenic patients and 33% amongst osteoporotic patients. Following fracture, 33% of patients were managed inadequately. The correlation between mammographic breast density and osteoporosis development proved to be statistically insignificant (p = 0.879). Conclusion: The majority of patients have been managed correctly and in accordance with bone health guidelines. Implications of these guidelines are highly beneficial to patients, and application may be deemed cost–effective. The correlation between mammographic breast tissue density and development of osteoporosis is insignificant, and should therefore not be clinically employed. Take-home message: As breast cancer survival increases emphasis must be placed upon improving quality of life, and there is no doubt that management of bone health and prevention of consequential fragility fractures is highly important and provides significant benefit to both patients and the NHS. Further research is required to refine management in the hopes of achieving an optimum.


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O37 Trials that consider omitting axillary clearance in patients with positive axillary sentinel node biopsy could potentiate under treatment T. Hussain, K. Grover, T. Mahapatra, P. L. McManus, A. Dhadda, P. J. Kneeshaw Castle Hill Hospital, East Riding of Yorkshire NHS Trust Introduction: The use of adjuvant radiation is a standard practice following

BCS and after mastectomy in selected patients. POSNOC trial is currently being designed to assess the effect of omitting ALNC in selected patients. The aim of the study was to identify the percentage of patients under-staged and not considered for PMRT or SCF RT with sentinel node metastasis if the POSNOC proposed protocol is followed. Methods: A total of 38 women found pre-operatively negative for axillary metastases but positive at SLNB and had ALNC were analysed. The absolute indication for PMRT or SCF RT in our study included 4 or more +ve lymph nodes (including sentinel nodes) and a tumour size of ≥5 cm. Fisher’s exact test was used to determine the statistical significance. Results: The mean age of the 38 patients was 55 years. 21% patients had T1, 76.3% T2 and 2.6% T3 disease. Percentage of positive SLNB was: 52.6% (1 node), 34.2% (2 nodes) and 13.1% (3 nodes). The number of positive nodes at clearance was: 0–3. If POSNOC inclusion criteria was considered, 23.6% (p = 0.0001) patients with ≥4 positive nodes (including SLNs) would have missed SCF-RT and PMRT. If multi-centric disease was in the POSNOC exclusion criteria, under-treated patients would reduce by 15.7%. Conclusion: Our study showed a significant risk of missing patients for chest wall or SCF radiotherapy with POSNOC protocol. Tumour multicentricity is an important factor to predict high axillary nodal involvement. Therefore, exclusion of T2 tumours with multi-centric involvement may be more appropriate. Take-home message: With the current imaging standards an accurate estimation of axillary disease pre-operatively remains subjective, varied and challenging. In such situations, under-staging of axillary disease is a real possibility. By considering omitting axillary clearance in patients with positive sentinel lymph nodes we may affect the indications for adjuvant radiotherapy. These patients then would then be at an increased risk of loco-regional recurrence.

O38 Identification and validation of a microrna signature associated with breast cancer progression PS Waters, RM Dwyer, P Hyland, C Brougham, D Wall, MJ Kerin Discipline of Surgery, Clinical Science Institute, University College Hospital, Galway, Ireland Introduction: MiRNAs are aberrantly expressed in the circulation of patients

with breast cancer. The aim of this study was to identify novel circulating markers indicative of disease progression. Methods: A murine model of basal breast cancer was established using athymic nude mice (n = 20) and MDA-MB-231 cell lines. Tumour volume was monitored weekly and blood sampling performed at weeks 1, 3 and 6 following tumour induction (total n = 60). Animals were sacrificed at week 6 and 10 microRNA arrays were preformed comparing animals with early (weeks 1, n = 5) versus late (week 6, n = 5) disease and results were analysed using RQ-PCR in all blood samples (n = 60). Reverse transcription for the relevant targets and endogenous controls was carried out and expression was quantified using RQ-PCR. 3 significantly dysregulated miRNAs were investigated in a patient cohort of breast cancer (n = 80). Results: Microarray analysis revealed 77 miRs to be significantly changed between week 1 and week 6 as disease progressed in a murine model. Top 10 dysregulated miRNAs were internally validated in the murine model.3 miRNAs were signifcantly dysregulated during tumour progression.miR-191 was unaltered in the patient cohort (p = 0.052). MiR-A was significantly

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upregulated in patients with cancer and furthermore increased in basal breast cancer (p < 0.05).miR106a was found to be significantly downrgulated in basal breast cancer and further decreased as tumours progressed from T1 to T4 disease (p < 0.05). Conclusions: This study highlights the importance of miRNAs in breast cancer. A murine model of basal breast cancer yields valid dyregulated miRNAs. Dysregulated circulating miRNAs during tumour progression have been identified. Take-home message: A murine model of basal breast cancer yields valid dysregulated miRNAs.

O39 Defining the value of diagnostic axillary ultrasound in early breast cancer – a contemporary cohort analysis H. Tuffaha, A. Gardiner, A. Lee, M. Reis, D. Brown, A. Evans, A. Thompson

Results: The mean age was 66 years (SD ± 13.05) with the survival data

available in 169 (53%) cases. Nuclear survivin was positive in 45% and showed positive correlation with ER and negative correlation with nodal status. Cytoplasmic survivin was positive in 76% and showed positive correlation with ER, PR and AR. On univariate analysis, neither nuclear nor cytoplasmic survivin was found to be a significant prognostic predictor for OS. There was no OS difference observed with nuclear (HR 1.35 (0.67, 2.69) or cytoplasmic survivin expression (HR 0.78 (0.27, 2.26) (Mean = 161 months, SD ± 14.45). Conclusion: In contrast to FBC, we were unable to show any prognostic role for nuclear or cytoplasmic survivin expression in a large cohort of MBC. Take-home message: In spite of its prognostic role in female breast cancer, neither nuclear nor cytoplasmic expression of survivin was shown to be a prognostic indicator in male breast cancer. This further supports the hypothesis of varying biological mechanisms involved in the development and progression of male breast cancer.

O41

Ninewells University Hospital, Dundee

The influence of intrinsic tumour subtype on breast cancer survival

Introduction: Preoperative axillary ultrasound (AUS) with needle biopsy and

pathology examination of nodes suspected of metastasis has become a standard of care in some centres. This study sought to demonstrate the value of a policy of axillary node ultrasound and biopsy in clinical practice. Methods: Clinically node negative women with symptomatic or screen detected breast cancer underwent review of a prospective policy of AUS at the time of diagnosis with core needle biopsy under local anaesthesia of nodes with a cortex >2 mm. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of AUS and biopsy were compared with pathology data post surgery. Patients with positive needle biopsy on AUS proceeded to level III axillary clearance; all others had sentinel lymph node biopsy (SLNB) with those positive on SLNB proceeding to clearance. Kolmogorov-Smirnov and Mann–Whitney tests for statistical significance were applied. Results: 390 patients were included in the study. 21.8% were AUS and pathology positive (mean 6.39 nodes, median 3, range 1–25; all nodes contained a macrometastasis). 78.2% were negative on AUS and proceeded to SLNB where 47/305 were positive and underwent clearance. AUS and core biopsy had a sensitivity of 64.4%, specificity of 100%, PPV 100% and NPV 84.6%. There was a significantly higher disease burden in AUS and core positive patients (p < 0.001). Conclusions: AUS in routine community practice can identify axillary disease in early breast cancer and select those patients with a disease burden likely to benefit from direct axillary clearance, thus reducing axillary reoperation. Take-home message: AUS accurately can select patients clinically node negative patients likely to benefit from surgical clearance of the axilla and thus reduce axillary reoperation.

O40

J. W. Walsh, A. M. McDermott, P. S. Waters, M. J. Kerin Discipline of Surgery, National University of Ireland, Galway Introduction: Breast cancer is a prevalent disease. Over the past decade

our understanding of its heterogeneity has advanced remarkably, with the identification of four distinct intrinsic subtypes, broadly classified by their receptor status. However, their prognostic significance has yet to be fully elucidated. The aims of this study were to investigate the impact of intrinsic subtype on overall and disease-free survival in breast cancer and to identify independent clinco-pathological predictors for disease recurrence. Methods: Hormone receptor status was determined on 433 patients newly diagnosed with breast cancer between 1993 and 2011 at our institution. Clinicopathological details of all patients were collated from a prospectively maintained database. Survival functions were performed. A log-rank test and multivariate test were performed using regression analysis to determine the factors associated with variables and their potential to act as predictors. Results: Mean age at diagnosis was 58.04 years. The cohort included the following; luminal A (n = 162), Luminal B (n = 70), HER2-overexpressing (n = 46) and Basal (n = 155). Median follow-up time was 60 +/−48 months. There were 104 deaths and 86 cases of disease recurrence. Luminal A and B tumours had significantly improved overall and local disease free survival (p < 0.05). Luminal A has signifcantly improved distant free survival (p = 0.001), Patients aged greater than 40 years and less than 5 postives lymph nodes had signifcantly improved local and distant disease free survival (p < 0.05). Conclusion: Intrinsic molecular subtype is a strong predictor of prognosis in breast cancer. Luminal A tumours are associated with the best overall survival and disease-free survival. Take-home message: Intrinsic molecular subtypes is a strong predictor of prognosis in breast cancer. Luminal A tumours are associated with the best overall survival and disease-free survival.

Survivin expression in male breast cancer S. S. Rajan1,2 , A. M. Hanby1,2 , K. Horgan2 , V. Speirs1 1 The Male Breast Cancer Consortium, Leeds Institute of Molecular Medicine, University of Leeds, 2 Leeds Teaching Hospitals NHS Trust, Leeds

Introduction: Survivin is a member of the inhibitor apoptosis family and has

been correlated with poor prognosis in female breast cancer. The prognostic role of survivin in male breast cancer was evaluated in this study and its expression was correlated against known clinical and pathological prognostic markers. Methods: Breast cancer tissue microarrays containing 319 tumours were stained using survivin antibody (D8; 1:50; Mouse monoclonal; Santacruz, CA). Both the extent (0 = 75%) and intensity (1 = mild; 2 = moderate; 3 = strong) of staining was used for cytoplasmic survivin expression, whereas only the extent for nuclear survivin. ROC was used to determine the optimum cut-off value for nuclear (≥ 1) and cytoplasmic survivin (≥ 3). Kaplan-Meier curves were plotted to determine the overall survival (OS).


O42 Conventional versus ultrasound-assisted liposuction in gynaecomastia surgery: A 13-year review K. Y. Wong, C. M. Malata Cambridge University Hospitals NHS Foundation Trust Introduction: Numerous surgical techniques exist for gynaecomastia

treatment. Although ultrasound-assisted liposuction (UAL) is thought to be more effective, there remains no objective and direct comparison with conventional liposuction. Hence, a comparative study was performed of a single surgeon’s experience over 13 years using two definitive parameters namely intraoperative conversion to open excision and postoperative revisional surgery rates.

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Methods: All gynaecomastia patients treated with UAL or conventional

liposuction (1999–2012) were retrospectively studied. UAL was only available in the private sector and was used for all such patients with no other selection or exclusion criteria. Results: A total of 219 patients (384 breasts) with a mean age of 29 years (range 12–74) were evaluated. UAL was utilised in 24% of breasts (47 patients, 91 breasts). Compared to traditional liposuction, UAL had significantly lower rates of intraoperative conversion to open excision (25% versus 38%; p < 0.05) and postoperative revision (2% versus 18%; p < 0.001) using Fisher’s exact test. The haematoma rate for each technique was 1%. Conclusion: UAL is a more effective treatment modality for gynaecomastia than conventional liposuction as determined by intraoperative conversion to open surgery and subsequent need for revision. Take-home message: Ultrasound-assisted liposuction is a more effective treatment modality for gynaecomastia than conventional liposuction as determined by intraoperative conversion to open surgery and subsequent need for revision.

O43 MiR-15 family microRNAs: Aberrant expression in breast cancer A. M. McDermott, H. M. Heneghan, D. Wall, N. Miller, M. J. Kerin Discipline of Surgery, National University of Ireland, Galway Introduction: Aberrant mi(cro)RNA expression has been demonstrated in

several disease states including breast cancer. The miR-15 family includes closely related miRNAs sharing common seed-sequences. The aim of this study was to profile the miR-15 family in blood and tissue of women with breast cancer and investigate their clinical utility as breast cancer biomarkers. Methods: Blood (n = 67) and tissue (n = 30) samples were collected from women with breast cancer following written informed consent. Blood samples were obtained from 57 healthy volunteers. MiRNA was extracted, reversetranscribed and miRNA expression quantified by RQ-PCR. Computational algorithms were used to select candidate mRNA targets, the expression of which was validated in breast tumours. Data-analysis was performed using qBase and Minitab software packages. Results: MiR-15a, miR-15b and miR-497 expression were lower in the circulation of breast cancer patients versus healthy controls (p = 0.001, 0.018, and 0.03) whereas miR-195 was upregulated in breast cancer patients (p = 0.001). In tissues, miR-15b, miR-195, miR-424 and miR-497 were dysregulated (p = 0.001, 0.001, 0.03 and 0.03 respectively). MiR-195 (p = 0.04, R = 0.64) and miR-497 (p = 0.04, R = 0.61) tissue expression correlated with that of the blood. Combination of circulating miR-15b/195/497 provided both a sensitivity and specificity of 79% for breast tumour detection. MiR-15 miRNAs have multiple cancer-related mRNA targets including BCL2, CCND1 and FGF2. Conclusion: This study is the first to examine circulating and tissue expression of the miR-15 family in breast cancer. The numerous remarkable properties of the miR-15 miRNAs, their altered expression patterns and potential role in breast cancer make them promising biomarkers in the future. Take-home message: MiRNA related research to date has largely focused on individual miRNAs, however, with such a significant similarity between family members we wished to determine what, if any, clinical relevance this transferred. The findings from this study suggest that the numerous remarkable properties of the miR-15 miRNAs, their altered expression patterns and potential role in breast cancer make them promising biomarkers and therapeutic targets in the future.

O44 PSMD9 expression predicts local recurrence following radiotherapy in breast cancer F. E. Langlands1,2 , D. Dodwell3 , A. M. Hanby4 , K. Horgan2 , R. A. Millican-Slater4 , E. T. Verghese1,4 , L. Smith1 , T. A. Hughes1 1 Leeds Institute of Molecular Medicine, University of Leeds, Leeds, 2 Department of Surgery, Leeds General Infirmary, Leeds, 3 St.James’s Institute of Oncology, St.James’s


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University Hospital, Leeds, 4 Department of Histopathology, St.James’s University Hospital, Leeds Introduction: Radiotherapy is a standard therapy used in the treatment of

breast cancer. Patient selection is based on clinicopathological risk factors with no consideration as to whether individual cancers are likely to respond to radiotherapy. Using predictive markers to select patients with tumours likely to respond to radiotherapy would reduce costly over-treatment and improve the risk-benefit ratio for the treatment, and could improve cancer outcomes. Previous studies (n < 50) report that tumour expression of the 26S proteasome, specifically the PSMD9 subunit, predicts response to radiotherapy: low PSMD9 expression was associated with higher rates of local recurrence after radiotherapy, suggesting that low proteasome expression and activity were associated with a degree of radio-resistance. However, this observation is at odds with the emerging use of proteasome inhibitors in cancer therapy as radio-sensitizers. Method: In a cohort of 157 breast cancer patients treated with and without postoperative radiotherapy we measured the expression of PSMD9 subunit. Results were analysed using SPSS V16.0 and PSMD9 was evaluated as a potential prognostic marker and predictive marker for radiotherapy. Results: High PSMD9 expression in tumour cells was significantly associated with increased incidence of local recurrence in patients receiving adjuvant radiotherapy (univariate log rank p = 0.02; multivariate regression p = 0.009) but not in those treated without radiotherapy. Conclusion: We conclude that PSMD9 expression may be a predictive marker for radiotherapy with high expression indicative of relative radio-resistance, the opposite of previous reports. Our conclusion warrants prospective confirmation but is entirely compatible with use of proteasome inhibitors as radio-sensitizers. Take-home message: There is an ongoing need for radiotherapy predictive markers. PSMD9 is a potential predictive marker that may have clinical utility in targeting therapy to the patients most likely to benefit.

O45 A combined analgaesic/anaesthetic intervention: Evaulating its effectiveness for the reduction of post-operative pain after breast cancer surgery J. Wormald, A. Figus, W. Notcutt, J. Pereira Norwich Medical School, University of East Anglia Introduction: Post-operative pain after breast cancer surgery is an

undertreated. This was confirmed by the results of the National Mastectomy and Breast Reconstruction Audit. There are numerous trials of single anaesthetic/ analgaesic interventions but there is a lack of evidence for the use of combined analgesic protocols in breast surgery. Methods: We conducted a questionnaire-based study evaluating the effectiveness of a standardised combined analgaesic/anaesthetic intervention (CA/AI). The study population consisted of breast cancer surgery patients undergoing the CA/AI and a control arm of patients undergoing routine care. Questionnaires were sent on the day of surgery and consisted of a verbal rating scale (VRS) and numerical rating scales (NRS) assessing pain in the first 24 hours and at one week. Results compared between the two groups. Relative risks were calculated using Chi-square tests and means were compared using Mann–Whitney U tests. Results: Forty-one patients (17 cases, 24 controls) responded to our questionnaire (response rate 57%). Post-operative pain was consistently lower in the CA/AI group at 24 hours and at one week. The CA/AI was more effective for mastectomy ± axillary surgery with the risk of moderate/severe pain reduced by 80% (RR 0.2). NRS scores were also consistently lower in the CA/AI arm for mastectomy ± axillary surgery and breast reconstruction. Conclusion: This preliminary report provides valuable pilot data that suggests a trend for a beneficial effect of the CA/AI for reducing post-operative pain in the first 24 hours and first week after breast cancer surgery when compared to routine care. Take-home message: This the preliminary report of an exploratory study of the effectiveness of a combined analgaesic/ anaesthetic intervention that shows potentially beneficial effects on post-operative pain after breast cancer surgery.

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O46

O48

Practical guidance for selection of sentinel node positive patients for further axillary surgery

Assessment of the axilla in breast cancer treated with neoadjuvant chemotherapy – how and when?

H. Tuffaha, A. Gardiner, A. Lee, M. Reis, D. Brown, K. Thompson, A. Thompson

T. McVeigh, D. Al-Azawi, D. E. Kearney, C. Malone, K. Barry, K. J. Sweeney, M. Keane, R. McLaughlin, M. J. Kerin

Ninewells University Hospital, Dundee

Galway University Hospital

Introduction: Practical guidance as to which patients with a positive sentinel

Introduction: Neoadjuvant Chemotherapy (NAC) is indicated for locally

node should be offered axillary clearance remains controversial. This study sought to identify key factors to guide the clinical team when to advise surgical clearance or radiotherapy for patients with a positive axilla on sentinel lymph node biopsy (SLNB). Methods: From July 2007- February 2012, 504 women underwent sentinel lymph node biopsy subsequently proceeding to axillary clearance for early breast cancer. Comparison of the primary cancer, patient and sentinel node features associated with subsequent pathology at axillary clearance were compared by Chi square and regression analyses. Results: 504 women, mean age 61.4 years underwent breast conservation surgery (87%) or mastectomy and SLNB. There was a 4.2% failure rate of the SLNB and 17.3% of patients were SLNB positive: 64 went on to axillary clearance; 9 radiotherapy and 14 (with ITCs or micrometastasis) no further action. 35 with a negative AUS had a positive SLNB. On univariate analysis tumour size >2 cm and extracapsular spread were the only features associated with subsequent positive nodes in the axillary clearance; only extracapsular spread remained significant on multivariate analysis. Conclusion: Extracapsular spread around a SLN would support the use of axillary clearance or therapeutic axillary radiotherapy. For other patients with tumour identified in the SLN, further axillary surgery may not be necessary. Take-home message: Not all patients with a positive sentinel node biopsy should proceed to axillary clearance.

aggressive invasive breast cancers, and affects the axilla as well as the breast. The aims of this study are to audit current practices in diagnostic assessment of the axilla in a cohort of patients undergoing NAC in advance of definitive surgery for breast cancer, and to identify the role and optimal timing of Sentinel Node Biopsy(SLNB). Methods: The study group included patients undergoing NAC for invasive breast cancer from 1999–2012. Data regarding patient demographics, tumour characteristics, nodal management and outcomes was obtained from a prospectively maintained database and analysed using PASW v18. Results: 204 patients were included. 102 underwent a diagnostic axillary procedure prior to commencing NAC, including 29 SLNB. Of these, 86 were noted to have metastatic axillary disease. In 34(40%) patients the axilla was found to be down-staged at Axillary Clearance (AXCn) post-NAC. Of 29 SLNB performed pre-NAC, 19 (66%) were positive. 18 proceeded to AXCn. Residual axillary disease was noted in only 9 (50%). 23 patients underwent SLNB post-NAC, of which 8 (35%) were positive. AXCn was performed in 7 patients, and residual disease noted in 5 (63%). SLNB post-NAC was negative in 15 patients. 6 proceeded to AXCn. 2(33%) were found to have residual disease. Conclusion: Assessment of the axilla in patients undergoing NAC remains controversial. Patients with positive SLNB post-NAC are more likely to have residual axillary disease at AXCn than patients with positive SLNB preNAC. However the effect of NAC on lymphatic drainage can impact its specificity. Take-home message: Axillary assessment performed after completion of Neoadjuvant Chemotherapy for breast cancer more closely correlates with final axillary status than axillary assessments performed prior to Neoadjuvant chemotherapy.

O47 Sentinel lymph node biopsy – are we downstaging the axilla? Z. M. Jessop, M. Oyewole, S. Deeba, E. D. Babu Department of General Surgery, Hillingdon Hospital

ORAL PRESENTATIONS 1B COLORECTAL

Introduction: Sentinel lymph node biopsy (SLNB) is the established technique

for axillary staging in patients with early breast cancer and clinically negative nodes. SLNB was introduced in our Trust in 2006 and following a validation period remains standard practice. Perceived reduction in positive nodes retrieved prompted us to investigate the sensitivity and false negative rate of SLNB. Methods: We retrospectively reviewed 300 consecutive patients with invasive breast cancer split into three cohorts; axillary dissection (n = 100), SLNB and axillary dissection during validation (n = 100) and SLNB alone (n = 100). They were compared with respect to demographics, primary procedure (mastectomy/wide local excision), histological type and grade of tumour, total number of axillary lymph nodes excised and number of positive nodes. Results: There were no significant differences in patient age, histological type or grade of tumour. The sentinel node was identified in 98.5% of cases (n = 200) with a median of two nodes in each specimen (range 0 – 10). A greater proportion of patients who underwent the traditional axillary dissection were found to be node positive compared to those with SLNB alone (56% vs. 11%; p = 0.0001, Fisher Exact Test). The false negative rate for SLNB was 18% (n = 100). Conclusions: Despite the good SLN localisation rate less axillary lymph nodes were positive for metastases following introduction of SLNB which cannot be explained in differences in type or grade of tumour. The low sensitivity (82%) raises concerns that our reliance on SLNB may mean we are downstaging the axilla. Take-home message: The low sensitivity of the sentinel lymph node biopsy technique in our Trust raises concerns that we may be missing positive axillary metastases.


O49 Awareness and uptake of family screening in patients diagnosed with colorectal cancer at a young age M. Hanley1 , N. M. Hogan1 , M. Sheehan2 , O. J. McAnena1 , M. Regan1 , M. R. Joyce3 1 Discipline of Surgery, School of Medicine, National University of Ireland, Galway, 2 Department of Histopathology and 3 Department of Colorectal Surgery, University

Hospital Galway 2 Introduction: About 15-20% of people who develop colorectal cancer have

a first-degree relative also affected by the disease. There is a large disparity in guidelines for screening of relatives of patients with colorectal cancer. We aimed to examine awareness and uptake of family screening amongst patients diagnosed with colorectal cancer under the age of 60 in a single institution between June 2009 and May 2012. Methods: Patients under the age of 60 who received surgical management for colorectal cancer at UCHG between June 2009 and May 2012 were identified using pathology records and theatre log books. A telephone questionnaire was carried out. Results: In total, 317 patients were surgically managed for colorectal cancer over the study period. 65 of these patients were under the age of 60 at diagnosis. 8

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patients were deceased and 13 declined to participate, leaving a study population of 44 patients. The mean age was 51 (range 30–59).66% had node positive disease. 25% had a positive family history of colorectal cancer, adenomas, and/ or polyps in a first degree relative. Of 324 living first degree relatives identified, only 40.9% had been screened as a result of patient’s diagnosis. Reasons for lack of uptake were diverse including unwillingness to undergo colonoscopy and fear of cancer diagnosis. Conclusion: Awareness and uptake of screening in first degree relatives of patients diagnosed with colorectal cancer at a young age is low. Increased education, uniformity of guidelines and dedicated family history clinics are needed to improve screening uptake in this high risk population. Take-home message: Guidelines for screening of first degree relatives of patients with colorectal cancer are diverse. Uptake and awareness are low in this high risk population.

O50 Neutrophil-lymphocyte ratio (NLR) as a simple and novel biomarker in predicting locoregional recurrence after chemotherapy for squamous cell carcinoma (SCC) of the anus E.-W. Toh, J. Wilson, I. Botterill, D. Sebag-Montefiore The John Goligher Colorectal Unit, St James’s University Hospital, Leeds

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Bidirectional crosstalk between stromal and epithelial populations is thought to be mediated by secreted proteins such as PAI-1. Although high circulating PAI-1 in CRC patients has been associated with poor prognosis, the specific source remains unknown. The aim of this study was to investigate interactions between MSCs and colorectal cancer cells and the factors mediating them. Methods: Cell-conditioned media containing all secreted factors was harvested from CRC cell lines (HT-29 and HCT-116) and MSCs. Absolute levels of PAI-1 were quantified using ELISA. Migration of CRC cellswas quantified in response to PAI-1 recombinant standards and MSC conditioned media with or without an antibody to PAI-1. Proliferation in the presence of these factors was also quantified using an MTS assay. Results: The highest levels of PAI-1 protein were secreted by stromal populations (range: 1.53-18.21ng/mL). CRC migrated towards PAI-1 protein standards (5-20ng/mL) and migrated in highest number towards MSC conditioned media containing all secreted factors. In the presence of an antibody to PAI-1, this migration was significantly decreased. Both HT-29 and HCT-116 proliferated to a greater degree, however PAI-1 had an anti-proliferative effect on HT 29 cells. Conclusion: This is the first study to report on the functional effects of MSCs on CRC cells. The pro-migratory and anti-proliferative effects of MSC-secreted PAI-1 reported here, suggests that MSCs have a significant impact on tumour biology. Take-home message: Mesenchymal Stem Cells are present in colorectal tumours and are having a distinct effect on proliferation and migration, mediated by PAI-1. These remarkable cells may represent novel therapeutic targets.

Introduction: NLR is a prognostic marker in several malignancies.This study

assesses whether NLR can be used as a predictor of locoregional recurrence after chemoradiotherapy for anal SCC. Methods: Patients treated with curative intent between 1st of January 2004 and 31st December 2011 were identified. Pre-treatment blood tests and radiological staging were available from multidisciplinary meeting records. NLR was calculated from pre-treatment blood tests. Relationships between NLR and clinico-pathological parameters were analysed. Receiver operating characteristic curves were constructed to determine the cut-off NLR to dichotomise the data for survival analyses.The measured cut-off NLR value was 4.75. Results: 92 patients were identified. Pre-treatment ’T’ stage was T1(n = 7),T2(n = 36),T3(n = 35) and T4(n = 14). Nodal stage was nodenegative(n = 62) and node-positive(n = 30). NLRs were significantly higher in both node-positive patients (p = 0.014) and cases who developed recurrence (p = 0.006). Elevated NLR(≥4.75) was predictive of recurrence at univariate level(Odds ratio[OR] = 10.67,95% Confidence interval[CI] = 3.2734.81, p < 0.0001) and multivariate level (OR = 9.59,95% CI = 2.85-32.34, p < 0.0001). On univariate survival analysis,an elevated NLR was associated with worse overall survival (Hazard ratio[HR] = 10.49, 95%CI = 2.7639.93, p < 0.0001) and cancer-specific survival (HR = 12.17, CI = 2.43-60.88, p < 0.0001). Multivariate Cox regression analysis demonstrated that an elevated NLR is a prognostic marker in overall survival (HR = 5.74,95% CI = 1.16-28.47, p = 0.032) but not in cancer-specific survival (HR = 2.51, 95% CI = 0.41-15.4, p = 0.319). Conclusion: Pre-treatment NLR is a simple clinical biomarker for predicting recurrence and overall survival after potentially curative treatment for anal squamous cell carcinoma. Take-home message: Pre-treatment NLR can be a simple and novel biomarker in predicting locoregional recurrence after curative chemotherapy for squamous cell carcinoma of the anus.

O51 Interactions between mesenchymal stem cells (MSCs) and colorectal cancer cells are mediated by plasminogen activator inhibitor type 1 (PAI-1) N. M. Hogan1 , R. M. Dwyer1 , M. R. Joyce2 M. J. Kerin1 1 Discipline of Surgery, School of Medicine, National University of Ireland, Galway and 2 Department of Colorectal Surgery, University Hospital Galway

Introduction: MSCs are known to home to and engraft at the site of colorectal

tumours. Despite this, their functional effect at this site has yet to be elucidated.


O52 KRAS mutation and its effect on outcome after neoadjuvant chemoradiotherapy in rectal cancer: A meta-analysis C. Clancy, J. P. Burke, J. C. Coffey University Hospital Limerick Introduction: Currently the gold standard of treatment for locally advanced

rectal cancer is neoadjuvant chemoradiotherapy (CRT) followed by total mesorectal excision. Some patients achieve a pathological complete response after neoadjuvant CRT whilst others have minimal response. Identification of biomarkers predicitng poor responders may avoid considerable morbidity in some patients. KRAS mutation,which is widely recognised as a key step in the adenoma-carcinoma sequence, has been investigated as a potential predictive biomarker in several studies however it has not been validated or incorporated into practice. Methods: A comprehensive search for published studies examining the effect of KRAS mutation and clinical outcomes after neoadjuvant chemoradiotherapy was performed. All chemoradiotherapy types and duration were recorded and interval to surgery was established. Random effects methods were used to combine data. Results: Data was retrieved from 9 studies describing 804 patients. KRAS mutation does not shorten disease free survival (odds ratio (OR): 1.239, 95% CI: 0.607-2.531, P = 0.555). It is not associated with decreased levels of pathological complete response (OR: 0.778, 95% CI: 0.424-1.428, P = 0.418) and does not decrease the likelihood of downstaging (OR: 0.846, 95% CI: 0.331-2.162, P = 0.728). Conclusions: The presence of KRAS mutation in rectal cancer is not predicitve of poor response to neoadjuvant CRT and does not decrease disease free survival or likelihood of downstaging. Take-home message: KRAS mutation does not confer additional resistance to neoadjuvant chemoradiotherapy in rectal cancer.

O53 Crohn’s disease: A population analysis of changing trends in hospital admission and surgical intervention 1995–2009 H. M. Mohan, A. C. Rogers, D. C. Winter Department of Surgery, St. Vincent’s University Hospital, Elm Park, Dublin 4, Ireland

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Introduction: The incidence of inflammatory bowel disease (IBD) is rising

Introduction: Laparoscopic colorectal surgery involves instrumented grasping

internationally. In addition, biological therapy has led to a paradigm shift in treatment strategies. Knowledge of changing trends in IBD is crucial in planning future acute hospital services. In this context, this study aims to evaluate trends in hospital admission and surgery for Crohn’s Disease in Ireland over 14 years from 1995 to 2009. Methods: Population-based analysis of national admissions and surgical intervention for Crohn’s Disease in Ireland using HIPE (Hospital Inpatient Enquiry) database and population data from the Central Statistics Office (CSO). Data was exported into Excel and analyzed using PAWS 18.0 SPSS. Results: Overall, Crohn’s Disease accounted for 48,142 admissions and 279,933 bed days during the 14-year study period. There was a significant increase in population adjusted admission rates over time for Crohn’s Disease (CD: 29.5/100000 in 1995, versus 43.6/100000 in 2009, p < 0.05) Populationadjusted admission rates of for major surgery rose significantly for Crohn’s Disease from 4.4/100000 in 1995 to 6.4/100000 in 2009. The mean age of major surgery did not change significantly over the study period (1995: 38.2 years, 2009: 40 years). Population adjusted day-case admissions for perianal surgery increased significantly (CD 1995: 0.1/10000, 2009: 1.5/100000). Conclusions: The number of admissions for surgery in Crohn’s Disease have not decreased; this may be due in part to the rising incidence of IBD. Although the total number of inpatient bed days remains high, there is a shift towards ambulatory care with increasing day case admissions. Take-home message: Population adjusted overall admissions and admissions for major surgical intervention in Crohn’s Disease have not decreased between 1995 and 2009.

of the colon with the risk of iatrogenic injury. We aimed to quantify colonic tissue recovery after mechanical stress application and correlate this with histological tissue damage. Methods: A 50kPA indentation was applied to fresh, ex vivo porcine colon using a modular universal surface tester (MUST) and held for 5, 30 or 60s on either the serosal or mucosal surface. Indentations were repeated 20 times. The difference between the highest and lowest force over the tissue relaxation period (F) was calculated. H&E staining was performed to grade colonic damage and compared to normal colon. The depth of each histological layer was compared to a control region. Results: The mean F was higher with indentations at the serosal as compared to mucosal surface at 5 and 30s time-points. This was reversed at 60s where F was higher at the mucosal surface. Histological analysis showed a significant decrease in muscle thickness at 5 (p = 0.03) and 30s (p = 0.001), irrespective of whether the force was applied to the mucosal or serosal surface. The submucosal depth was decreased in the 60s indentations only (p = 0.001). A positive correlation was observed between indentation duration and grade of mucosal injury. Conclusions: We have shown for the first time that mechanical stresses, equivalent to those in laparoscopic tissue grasping, result in microscopic damage to the colon. The extent of irreversible damage is dependent on the duration of applied stress. Further analysis is being undertaken to determine safe thresholds for tissue handling. Take-home message: Mechanical stresses, equivalent to those in laparoscopic tissue grasping, result in microscopic damage to the colon in ex vivo experiments.

O54

O56

Increased dermal elastic fibres in patients with rectal prolapse

A potential pathway linking inflammation to miR-21 activation and PDCD4 downregulation in colorectal cancer

H. M. N. Joshi, E. A. Smyth, O. Jones, C. Cunningham, J. Urban, I. Lindsey

O. Peacock, F. Cameron, A. Lee, C. Tufarelli, J. Lund

Oxford Pelvic Floor Centre Introduction: The aetiology of rectal prolapse is not well understood. A

number of studies have suggested that there may be an underlying connective tissue disorder contributing to the condition. The skin is a ‘‘window’’ into connective tissue disorders. We aimed to determine whether dermal elastic fibres are altered in patients with rectal prolapse. Methods: Dermal punch biopsies were taken from prolapse and control patients. The samples were histologically processed to identify elastic fibres. Image analysis software was used to quantify the percentage surface area occupied by elastic fibres. Control patients underwent resections for rectal cancer. Results: (Data presented as median, range +/−SD): Controls had lower levels of elastic fibres (4.0% )(3.88- 5.56 +/−0.80) than nulliparous women (7.8%)(5.67-11.72 +/−2.21) p 0.02, multiparous women (7.4%)(2.32-22.11 +/−3.95)p 0.01 and men (8.3%)(6.83-13.22+/− 2.5) p0.01. In multiparous women, those with external prolapse had more elastic fibres (8.0%) (6.57-22.11 +/−5.65) than those with internal prolapse (7.2%) (2.32- 13.22 +/− 2.52) p 0.04. Conclusion: Patients with rectal prolapse have higher amount of dermal elastic fibres compared to controls. This may be indicative of further biological evidence of a generalised connective predisposition to developing the disorder. Take-home message: Development in characterising the pathophysiology of rectal prolapse.

O55 Analysis of colon damage and recovery following application of a mechanical stress J. Barrie1 , S. Hafeji, P. Culmer1 , A. Neville1 , D. G. Jayne2

Division of Surgery, School of Graduate Entry Medicine & Health, University of Nottingham, Royal Derby Hospital Introduction: Aspirin is effective in chemoprevention of colorectal cancer

(CRC). The mechanisms underlying this effect are unclear but may partly rely on its ability to inhibit cyclooxygenase (COX) enzymes. COX-2 is an important player in tumour development and alters the expression of the tumour suppressor gene Programmed Cell Death 4 (PDCD4). As PDCD4 is also a direct target of the oncogene microRNA-21 (miR-21), we aimed to investigate a potential pathway involving COX-2, miR-21 and PDCD4. Methods: miR-21, PDCD4 and COX-2 expression were measured using quantitative RT-PCR in tumour and paired normal mucosa tissues from 45 CRC patients and correlated to tumour stage. Expression analysis of miR-21, PDCD4 and COX-2 was also performed on HCA-7 CRC cells before or after treatment with anti-miR-21, or a selective COX-2 inhibitor (NS398), or Prostaglandin E2 (PGE2). Results: Upregulation of miR-21 (p < 0.0001) and COX-2 (p < 0.0001) mRNA and downregulation of PDCD4 mRNA (p < 0.0001) in CRC tissue relative to paired normal mucosa was demonstrated, correlating with worse Duke’s stage (p < 0.0001). In HCA-7 cells, knockdown of miR-21 and treatment with NS398 significantly increased PDCD4 protein levels (p < 0.01 and p < 0.001 respectively). NS398 had no effect on miR-21 expression whilst PGE2 upregulated miR-21 expression and downregulated PDCD4 protein (p = 0.02). Conclusion: Significant changes of miR-21, PDCD4 and COX-2 RNA levels in CRC correlate with worsening stage and appear functionally related. COX-2 induced downregulation of PDCD4 in CRC may be achieved via PGE2 and miR-21 dependent and independent pathways which are worthy of further investigation as potential therapeutic targets. Take-home message: This is the first study to demonstrate a potential pathway linking inflammation with miR-21 activation and downregulation of the tumour suppression gene PDCD4 in colorectal cancer.

1 School of Mechanical Engineering, The University of Leeds, 2 Division of Clinical

Sciences, Leeds Institute of Molecular Medicine, The University of Leeds


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O57 Comparison of anal evoked potentials elicited by mechanical and electrical stimuli in anaesthesised rats J. Evers1 , E. V. Carrington1,2 , S. M. Scott2 , C. H. Knowles3 , P. R. O’Connell4 , J. F. X. Jones1 1 School of Medicine and Medical Science, University College Dublin, Dublin, Ireland, 2 GI Physiology Unit, The Wingate Institute of Neurogastroenterology, Queen Mary, University of London, London, 3 National Centre for Bowel Research and Surgical

Innovation, Queen Mary, University of London, London, United Kingdom, 4 Centre for colorectal disease, St Vincent’s University Hospital, Dublin, Ireland Introduction: Evoked potentials (EPs) can be used to interrogate sensory

pathways fundamental to control of defaecation, but are usually elicited using electrical stimuli known to activate multiple neuronal subtypes. Use of a physiological stimulus would provide a more accurate assessment of those pathways. This study compared mechanical and electrical EPs of the rat anal canal. Methods: Eight anaesthetised female Wistar rats (body mass 180-270g) were used to record EPs using a 32 channel multi-electrode array overlying the right primary somatosensory cortex. Electrical EPs were elicited using a 2mm anal plug electrode (1Hz, 1ms, 10V) and mechanical EPs using an inter-dental brush placed on a rotating stepper motor (1Hz, 1ms, 15o rotation). Response latency, amplitude and spatial extent, expressed as an index, were measured. Statistical significance was assumed if P < 0.05. Results: Mechanical and electrical EPs were successfully recorded in all animals. Mean maximal response amplitude (electrical 30.8µV (SD 27.8) vs. mechanical 17.5 (11.5)) and onset latency (electrical 14.1ms (3.5) vs. mechanical 13.7 (1.5)) were similar (Student’s t-test P = 0.17 and P = 0.83). Cortical location and waveform profile were also comparable. The spatial extent index was lower for mechanical stimulation (2.5 (1.7) vs. (4.1 (2.5)), but did not reach statistical significance (P = 0.06). Conclusions: To the authors’ knowledge these are the first mechanically elicited anal EPs recorded in animals. Characteristics appear similar to those elicited electrically. Mechanical EPs may prove useful in the further exploration of treatments that modulate the neuronal control of defaecation such as sacral nerve stimulation. Take-home message: Characteristics of mechanically and electrically evoked anal potentials are similar. As mechanical stimulation provides a more physiologic stimulus, these may be useful in the exploration of anal sensation.

O58 Carcinoembryonic Antigen (CEA) is a highly specific and sensitive marker for colorectal cancer in vivo imaging or targeted delivery applications and outperforms other candidate markers

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CI 10.31-11.21), compared to the next best marker, TAG-72 (mean 5.1, 95% CI 4.35-5.77). FRα and EGFR showed only small increases in expression within tumours. Similarly, CEA showed the greatest differential expression between positive and negative lymph nodes. The sensitivity and specificity of each marker for detecting tumour tissue were determined following receiver operating characteristic analyses; CEA gave the best combination of 93.7% and 96.1% respectively. Conclusion: CEA has the greatest potential to allow highly specific tumour imaging and drug delivery; future translational research should aim to exploit this. Take-home message: EGFR, TAG-72, CEA and Folate Receptor alpha have all been used as colorectal cancer-specific targets for intra-operative imaging, targeted-PET/MRI and selective cytotoxic drug delivery. CEA has the greatest potential as a highly sensitive and specific target for these applications.

O59 Does tumour tattooing in colorectal surgery affect lymph node yield? R. M. Evans, P. Mummugati, M. Davies, M. D. Evans, T. V. Chandrasekaran, U. Khot, J. Beynon, D. A. Harris Dept of Surgery, Singleton Hospital, Swansea Introduction: It is common practice to routinely tattoo colorectal neoplastic

lesions to facilitate detection at laparoscopic resection. It is frequently observed that mesocolic lymph nodes avidly uptake the blue dye which may facilitate subsequent detection by the pathologist. The aim of this study was to determine if total lymph node harvest in resected cases is higher in those patients with tattooed tumours. Methods: Patients having laparoscopic resection between 2004–2010 were identified from a prospective database. Presence of tattoo, diagnosis, operative procedure and lymph node yield (total and involved) were collected. Statistical analysis was by one-way ANOVA. Results: One hundred and forty one patients were studied including 84 malignant cases (60%). 89 cases (63%) were tattooed. Mean total node yield was 15.4 in anterior resection, 11.9 left hemicolectomy and 16.3 for right hemicolectomy (p = 0.06). Mean total node yield was lower in benign cases compared with malignant (9.9 vs. 17.3) (p = 0.0001). Overall there was no significant difference in total mean lymph node yield in tattooed cases (14.4) compared with non-tattooed cases (15.3, p = 0.513). Separate analysis of malignant cases in the series showed no significant difference in total node yield (16.06 tattoed vs. 18.09 non-tattoed, p = 0.27) or involved node yield (1.97 tattoed vs. 1.6 tattooed, p = 0.577). Conclusions: High rates of lymph node harvest were observed in this series of laparoscopic colorectal resections. Preoperative tumour tattooing did not correlate with increased total or involved lymph node yield. The utility of this technique in improving node harvest in centres with low nodal yield warrants investigation.

J. P. Tiernan1,2 , S. L. Perry1 , E. T. Verghese1,2 , N. P. West1,2 , S. Yeluri2 , D. G. Jayne1,2 , T. A. Hughes1

O60

Leeds Institute of Molecular Medicine 1 , Leeds Teaching Hospitals 2 Introduction: Colorectal cancer-specific biomarkers have been used as targets

for fluorescent intra-operative imaging, targeted PET/MRI and selective cytotoxic drug delivery. Each of these applications is reliant upon tumourspecific markers, yet marker selection is rarely evidence-based. We evaluated the sensitivity and specificity of potential markers for colorectal cancer detection to inform these choices. Methods: Carcinoembryonic antigen (CEA), tumour-associated glycoprotein72 (TAG-72), folate receptor alpha (FRα) and endothelial growth factor receptor (EGFR) were identified as the markers most commonly used in published work. Their expression was evaluated by immunohistochemistry in matched normal and tumour tissue from 280 patients using Histoscores of 0–15. Matched positive and negative lymph nodes from 18 patients were also examined and scored. Results: Markers were more highly expressed in tumour tissue than in matched normal tissue in 98.8%, 79.0%, 37.1% and 32.8% of cases for CEA, TAG-72, FRα and EGFR respectively. CEA showed the greatest differential expression, with tumours scoring a mean of 10.8 points higher than normal tissues (95%


Reporting of long-term survival and oncological outcomes of colorectal cancer surgery: A systematic review R. O. Forsythe1 , R. N. Whistance1,2 , A. G. K. McNair2 , S. T. Brookes2 , K. Avery2 , A. M. Pullyblank3 , D. G. Jayne4 , J. M. Blazeby1,2 on behalf of the CONSENSUS-CRC (Core Outcomes and iNformation SEts iN Surgical Studies – ColoRectal Cancer) working group 1 Division of Surgery Head and Neck, University Hospitals Bristol NHS Foundation Trust, 2 Academic Unit of Surgical Research, School of Social and Community Medicine, University of Bristol, 3 Department of General Surgery, North Bristol

NHS Trust, 4 Academic Surgical Unit, St James’ University Hospital NHS Trust, Leeds Introduction: Assessment of survival rates and disease recurrence is important

to inform treatment decisions in patients with colorectal cancer (CRC). There is currently no consensus, however, on how these outcomes should

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be measured. This study aimed to consider the verbatim terms and definitions of long-term survival and oncological outcomes reported in studies of CRC surgery. Methods: This systematic review identified prospective studies of CRC surgery between 2009–2010. Excluded were studies of non-biomedical interventions; non-curative, non-surgical treatments; screening; and treatment of colorectal metastases. Data extraction included the verbatim terms and definitions of survival and long-term oncological outcomes. Results: Some 5644 abstracts were identified of which 194 articles (34 randomised and 160 non-randomised studies) were included. 766 different clinical outcomes were extracted from publications of which 42 pertained to long-term survival and 66 to oncological outcomes. The most frequently reported survival outcomes were ‘overall survival’ (recorded in 60, defined in 20 in 6 different ways) and ‘disease-free survival’ (recorded in 43, defined in 27 in 16 different ways). The most frequently reported oncological outcomes were ‘local recurrence’ (recorded in 44, defined in 19 in 15 different ways) and ‘distant recurrence’ (recorded in 23, defined in 4 in 4 different ways). Conclusions: Long-term survival and oncological outcomes of CRC surgery are inconsistently reported and poorly defined. Standardisation of outcome reporting is necessary to improve data synthesis, allow comparisons between studies and to better inform clinical practice. We recommend the development of a core outcomes set (a minimally reported set of endpoints for all studies of CRC surgery). Take-home message: Standardisation of outcome reporting is necessary to improve data synthesis, allow comparisons between studies and to better inform clinical practice. We recommend the development of a core outcomes set (a minimally reported set of endpoints for all studies of CRC surgery).

O61

Introduction: Genetic and epigenetic factors are implicated in the

pathogenesis of colorectal cancer and may predict the response to treatment. This pilot work aims to implicate which of these factors determine the response of rectal cancer to neoadjuvant chemoradiotherapy. Methods: Patients undergoing neoadjuvant chemoradiotherapy and subsequent resection for rectal adenocarcinoma were identified. Pretreatment biopsies were analysed by immunohistochemistry for DNA (cytosine-5)methyltransferase (DNMT1) and 5 Methyl Cytosine (5MC). KRAS mutations (codon 12,13,61) were detected using pyrosequencing. CpG island methylator phenotype (CIMP) status was determined by methylation specific PCR using a two panel approach. Tumour regression grade (TRG) was analysed by two independent histopathologists. Results: 24 patients were analysed initially. 6/24 (25%) were CIMP-High, 5/24 (21%) CIMP-Intermediate and 13/24 (54%) CIMP-Low. 4/6 (66%) CIMP H tumours had KRAS mutations, compared with 3/13 (23%) CIMP L. Tumour regression was less marked in CIMP H tumours (mean TRG 2.83/5) compared with CIMP I (mean TRG 3/5) and CIMP L (mean TRG 3.45/5). DNMT1 staining scores were similar between groups but 5MC staining scores were higher (mean score 7.4/8) in CIMP H tumours compared with CIMP L tumours (mean score 6/8), which approached statistical significance (p = 0.08). Extra mural vascular invasion was seen in 3/24 tumours, all of which were CIMP-H. CIMP H tumours were associated with advanced T and N stage. Conclusions: High levels of tumour methylation correlate with adverse pathological features. CIMP status as a marker of aberrant DNA methylation demonstrates potential as a predictive marker for patients response to neoadjuvant chemoradiotherapy and may have utility in guiding neoadjuvant treatment. Take-home message: Preliminary data from this study suggest that characterisation of DNA methylation status and KRAS mutational analysis in pretreatment biopsy specimens may offer a useful tool in predicting patients response to neoadjuvant chemoradiotherapy.

Systemic inflammatory response is predictive of outcome in patients undergoing surgery for locally recurrent rectal cancer

ORAL PRESENTATIONS 1C HPB SURGERY

D. P. Harji, B. Griffiths, J. Sarveswaran, M. Evans, A. Koshy, P. M. Sagar St James’s University Hospital, Leeds Introduction: Systemic inflammatory response is associated with outcomes

in a number of malignancies. We investigate the predictive value of markers of SIRS as potential biomarkers of outcome in patients with locally recurrent rectal cancer (LRRC). Methods: Patients undergoing surgery between January 2005 and December 2011 were identified. Data on pre-operative neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), C-reactive protein, albumin and haemoglobin (Hb) were collected. Results: One hundred and thirty patients were identified. At ROC analysis, NLR of 4.81, PLR of 233, Hb of 13.1, Albumin of 26, and CRP of 8.1 had the highest sensitivity and specificity. Elevated NLR, PLR and CRP were associated with poor overall survival (p < 0.05). NLR and margin status were the only prognostically significant factors at multivariate analysis (p < 0.05). Conclusions: This study has highlighted the importance of NLR, PLR and CRP in influencing post-operative outcomes in patients with LRRC. Preoperative inflammatory markers are important clinical biomarkers associated with tumour biology and prognosis in patients with locally recurrent rectal cancer. Take-home message: The inflammatory response is important in predicting outcomes in patients with locally recurrent rectal cancer.

O62 Genetic and epigenetic factors in prediction of response of rectal adenocarcinoma to neoadjuvant chemoradiation J. S. Williamson, W. N. Williams, A. P. Griffiths, C. Davies, G. J. Jenkins, J. Beynon, D. A. Harris Department of Colorectal Surgery, Abertawe Bro Morgannwg University Health Board


O63 Increased expression of toll-like receptor (TLR) 4 and TLR5 following complex hepato-pancreatico-biliary (HPB) surgery predicts the development of post-operative systemic inflammatory response syndrome (SIRS) R. Lahiri1,2 , J. Wong1 , J. Waters1 , S. Bhattacharya2 , G. Foster1 , W. Alazawi1 1 Department of Hepatology, Centre for Digestive Diseases, Barts and the London School of Medicine and Dentistry, Queen Mary, University of London, 4 Newark Street, London, E1 2AT, United Kingdom, 2 Barts and the London HPB Centre, Barts Health NHS Trust, Stepney Way, Whitechapel Road, London, E1 1BB

Introduction: Patients undergoing major oncological resections are at risk

of life-threatening post-operative sepsis and systemic inflammatory response syndrome (SIRS). Early identification of patients who are at high risk would allow for tailored post-operative care. This study investigated the changes in monocyte TLR4 and TLR5 expression following surgery and correlated these with inflammatory complications following major HPB surgery. Methods: Serial blood samples were taken from 20 patients (10 male, mean age 64.3 years) undergoing major HPB surgery pre-operatively and on days one and two postoperatively. Patients with inflammatory co-morbidities, pre-operative sepsis and taking anti-inflammatory medication were excluded. Peripheral blood mononuclear cells (PBMCs) were isolated and stained with CD14, TLR4 and TLR5 antibodies. CD14 positive cells were evaluated for TLR4 and TLR5 expression (mean fluorescent intensity (MFI)) by flow cytometry. Patients were followed-up for 7 days and inflammatory complications were recorded. SIRS was defined by the American College of Chest Physicians/Society of Critical Care Medicine consensus criteria.

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Results: Five patients developed SIRS on day five or later. Early post-

operative TLR4 and TLR5 expression on monocytes were significantly greater in patients who developed inflammatory complications (day 1: MFI; 4864 vs 1863; p < 0.0001) (day 2: MFI; 4983 vs 2939; p < 0.0001) than in those who had an uneventful recovery. There were no significant differences in pre-operative TLR4 and TLR5 expression (p < 0.16). Conclusion: High levels of monocyte TLR4 and TLR5 expression in the early post-operative period helps to identify patients who will subsequently develop SIRS. SIRS - systemic inflammatory response syndrome PBMC - peripheral blood mononuclear cell MFI - mean fluorescence intensity Take-home message: Increased expression of TLR4 and TLR5 on monocytes can help to identify patients who will develop SIRS after major surgery.

O64 Does sequential complete embolization of inflow to liver result in improved FLR augmentation? R. Lochan1 , S. Robinson1 , J. J. French1 , B. C. Jaques1 , J. Rose2 , R. M. Charnley1 , D. M. Manas1 , S. A. White1 1 Department of HPB Surgery and 2 Radiology Freeman Hospital

Introduction: Portal vein embolisation (PVE) is an established technique

to increase the future liver volume/remnant (FLR) prior to liver resection. For those patients where hypertrophy is insufficient, further hepatic artery embolization (HAE) has been suggested. Methods: We interrogated a prospectively maintained database to identify patients who had undergone FLR augmentation after discussion at a MDT meeting. The aim of this study was to evaluate the feasibility/safety of PVE with sequential HAE over a 5-year period (Jan 2006 –May 2011). Results: 50 patients (M: F = 38:12) underwent a right PVE; 33 (66%) progressed to liver resection. The median FLR of these patients, by CT volumetry, was 384.5 cc (330–490). Reasons for inoperability (34%) following PVE (n = 17) were 1) Small FLR, (n = 6) all underwent HAE (with 5 proceeding to liver resection) 2) progressive disease (n = 11). HAE increased FLR by a further 80.8 cc (26–100). An R0 resection was achieved in 25 patients (76%), including 4/5 (80%) of sequential patients. Following PVE and sequential embolization; 9/33 (27%) and 3/5 (60%) suffered serious complications (Clavien-Dindo 3/4). Six post-operative deaths occurred [5/33 (15%) after PVE, 1/5 (20%) following sequential embolization]. Conclusion: PVE allows a significant proportion of patients to attain an R0 resection despite initially being considered inoperable. Nevertheless at least 20% of patients will have progressive disease. Patients who do not achieve adequate hypertrophy after PVE can potentially have HAE to increase the FLR by a further 100cc but perhaps at the expense of increasing post-operative complications. Take-home message: Further inflow embolisation is an option to be considered in patients with inadequate FLR following PVE, provided there are no other limitations to curative resection.

O65 Prognostic implications of tumour-associated lymphocytes in pancreatic ductal adenocarcinoma and extrahepatic cholangiocarcinoma N. Tewari1,3 , A. M. Zaitoun2,3 , A. Arora4 , S. Madhusudan4 , M. Ilyas2 D. N. Lobo1,3 1 Division of Gastrointestinal Surgery, University of Nottingham, 2 Department of Cellular Pathology, Nottingham University Hospitals NHS Trust, 3 NIHR Nottingham Digestive Diseases Centre Biomedical Research Unit, 4 Academic Oncology,

University of Nottingham, School of Molecular Medical Sciences, Nottingham University Hospitals NHS Trust

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been evaluated in this tumour group. We evaluated the prognostic significance of CD3, CD8 and CD20 positive lymphocytes in pancreatic and biliary tract cancers. Methods: One hundred and ninety one patients with surgically resected cancers of the pancreas and biliary tract were included. Tissue micro-arrays were constructed and immunohistochemistry performed for CD3, CD8 and CD20. The number of lymphocytes within tumour compartments (stromal and intra-tumoural) was quantified. Multiple regression analysis was performed to assess correlation of TALs with clinicopathological features and survival. Results: CD3 and CD8 positive lymphocytes were associated with perineural invasion and increased tumour size in pancreatic adenocarcinoma. In cholangiocarcinoma, the presence of CD3 positive lymphocytes in the stroma was not significantly related to tumour size (p = 0.087) but there was correlation between tumour size and the presence of CD20 positive lymphocytes (p = 0.003). Presence of intratumoural CD3+ cells in pancreatic adenocarcinoma was associated with improved survival (p = 0.023). The presence of CD3 positive and CD8 positive T-lymphocytes and CD20 positive B-lymphocytes in combination correlated with improved survival in pancreatic cancer (p = 0.021). There was no association between presence of TALs and survival in cholangiocarcinoma (p = 0.672). Conclusion: A positive correlation was demonstrated between the presence of TALs and survival in pancreatic cancer but not in cholangiocarcinoma. Take-home message: In cholangiocarcinomas and pancreatic adenocarcinoma, the presence of tumour-associated lymphocytes in resected specimens may have prognostic implications.

O66 Pancreatico-duodenectomy with vascular resection for locally advanced pancreatic cancer. Is there a survival advantage? A. Amer, J. French, B. Jaques, R. Charnley, D. Manas, S. White Newcastle upon Tyne Hospitals NHS Trust Introduction: Surgical resection remains the only curative option for

pancreatic cancer. With recent advances in peri-operative care, complications from pancreatico-duodenectomy with vascular resection (PDVR) are now comparable to those from standard pancreatico-duodenectomy (PD). However, the survival benefit of performing PDVR compared to standard PD or even a palliative bypass remains debatable. We aim to compare the survival outcome between patients undergoing standard PD, PDVR, and surgical bypass (SB) for locally advanced ductal adenocarcinoma of the pancreatic head. Methods: A retrospective cohort study including all patients that underwent a Whipple procedure or surgical bypass for locally advanced pancreatic ductal adenocarcinoma over a 10-year period at a single pancreatic centre. Data collected included background demographics as well as perioperative parameters and follow up/survival outcomes. Comparisons between groups were made using overall and disease-free survival rates and Kaplan-Meier survival analysis. Results: Of 228 patients included in this study, 53.1% underwent PD while 20.6% underwent PDVR. Palliative SB was performed in 26.3% of cases. No significant differences were found between the groups in terms of demographics, histological findings or postoperative complication rates. Six-month, 1-, 2- and 3-year overall and disease-free survival rates were not significantly different between the PD and PDVR groups, whereas overall survival rates in surgical bypass cases were significantly lower than the two resection groups (6-month overall survival: PD = 85.1%, PDVR = 91.5%, SB = 60%; 3-year survival: PD = 17.4%, PDVR = 12.8%, SB = 0%). Conclusion: PDVR confers a survival advantage over SB in stage III disease with vascular involvement, with survival and complication rates comparable to PD alone. Take-home message: PDVR confers a survival advantage over SB in stage III disease with vascular involvement, with survival and complication rates comparable to PD alone.

Introduction: Cancers of the pancreas and the bile duct have a 5-year survival

rate of less than 5%. Tumour associated lymphocytes (TALs) are associated with good prognosis in several solid tumours but have not been previously


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O67

Take-home message: This study, with the use of cadaveric dissections,

Oncological feasibility of laparoscopic distal pancreatectomy for adenocarcinoma of distal pancreas: A single-institution comparative study

has shown that variation does exist in the patterns of origin of the inferior pancreaticoduodenal arteries, and that variation also exists in the level at which the inferior pancreaticoduodenal arteries arise from the SMA. This knowledge is important because the single most important detail during a multi-organ procurement is retention of the inferior pancreaticoduodenal arteries with the pancreas as it is essentially the only bloody supply to the head of a transplanted pancreas.

S. Rehman, R. Lochan, J. J. French, B. C. Jaques, D. M. Manas, S. A. White Department of Hepatobiliary Surgery, Freeman Hospital Introduction: Laparoscopic distal pancreatectomy (LDP) is standard

procedure for resection of distal pancreatic pathology. However, concerns have been raised regarding its oncologic adequacy in treating pancreatic malignancies as compared to open distal pancreatectomy (ODP). The aim of this study was to explore this issue. Methods: We retrospectively analysed a prospectively maintained Unit database for patients who underwent distal pancreatic resection between Jan 2005 and March 2012. Data was analysed on SPSS v19 utilising standard tests. A p-value of 6 were extracted and collated and an assessment form was developed. This was piloted and internal consistency was determined by Cronbach’s α, and inter-rater reliability by interclass correlation coefficient, ICC (significance = p < 0.05). Since there was no gold standard, construct and criterion validity could not be assessed. Results: 43 interviews were performed (29 trainers, 10 trainees, 4 educationalists), and analysis and item creation showed excellent inter-rater agreement (Cohen’s κ = 0.92). Lists were distributed to 11 NTP trainers and 7 trainees and consensus reached after two rounds. Focus groups and piloting created a 64-item assessment (23 iterations), that once completed by an observer in real-time during a training episode, could provide feedback to the trainer regarding their training structure, behaviour, attitudes and role modelling (Structured Training Trainer Assessment Report (STTAR). There was good face and content validity, internal consistency (α = 0.88), interrater reliability (ICC = 0.75), and the tool was accepted as feasible and useful [median score 4 of 5 (IQR 1–5)]. Conclusions: A reliable, valid educational assessment tool that is uniquely comprehensive in evaluating training has been designed and implemented into the NTP. Its transferability to other medical specialties should be investigated. Take-home message: The STTAR is a novel educational tool that objectively quantifies teaching in terms of its structure, delivery and the trainer’s attributes and non-technical skills, thereby providing focussed individual feedback.

O80 Anatomy knowledge in core surgical trainees T. Jennison West Midlands Deanery Introduction: Anatomy knowledge for surgical trainees is vital. A good

knowledge of anatomy can enable the trainee to get the most out of the surgical opportunities available. Many Consultants argue that the standard of Anatomy has decreased in recent years in medical schools and trainee surgeons. There is considerable variation in provision of anatomy teaching to core surgical trainees from regular prosection sessions to no anatomy teaching at all in some

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instances. The aim of this study was to assess surgical knowledge in new Core Surgical Trainees (CT1). Methods: An 11 question anatomy survey was distributed during a CT1 Teaching session. Results: 22 CT1 Doctors completed the questionnaire. The mean score out of 11 was 6.7 (60.7%), with a range between 3 and 9 (27.3%-81.8%). Doctors fared worse on questions on the layers of the scrotum, boundaries of Calot’s triangle and the boundaries of the inguinal canal, with less than 40% of correspondents answering correctly. The trainees scored best on labelling the bones of the foot and rotator cuff muscles (95% correct). Of the responders only 31% felt they had sufficient anatomy knowledge to commence core surgical training, and over 95% wanted prosection sessions to be included in the teaching curriculum. Conclusion: The anatomy knowledge of Core Surgical Trainees was below the standard expected. The majority of Doctors agreed that they did not have a good enough grasp of anatomy for surgical training, and feel additional anatomy teaching should be a standard part of the core surgical training programme. Take-home message: The anatomy knowledge of Core Surgical Trainees was below the standard expected. Anatomy teaching should become a mandatory part of the Core Surgical Training program in all Deaneries.

O81 A prospective survey of surgical handover practices and outcomes in the United Kingdom

and clinical results in structured mentored laparoscopic colorectal training programmes. Methods: All cases submitted to Lapco by consultant Lapco trainees and Ethicon Fellows between July 2008 and May 2012 were analysed. Poor training cases were detected using a validated assessment form of training quality, completed by trainees for each case. Binary Logistic regression was used to identify which factors predicted a poor training case and to identify the predictors of conversion. Mann–Whitney U tests were used to compare clinical outcomes. Results: 483 of the 2341 cases analysed were identified as poor training cases. The significant predictors of a poor training case were male gender, pelvic resections and conversion. Predictors of conversion were ASA class 3 or 4, male gender (a strong predictor of conversion in all resection types), BMI > 30, prior abdominal surgery, the presence of adhesions or abscesses and pelvic and leftsided resections. Surgeon experience didn’t predict conversion rate, however as experience increased they selected more complex cases. Poor training cases had significantly higher rates of abdominal complications, re-operation and re-admission, but not mortality. Conclusions: Case selection is important during mentored training in laparoscopic colorectal surgery. Inappropriate case election leads to poor training and adversely effects clinical outcomes, despite the presence of an expert mentor. Lapco – National Training Programme for laparoscopic colorectal surgery. Take-home message: Whilst training in training in laparoscopic colorectal surgery case selection is important to optimise learning and minimise patient morbidity.

Q. Frew, C. Allen, S. Siddiqui, J. Ford, J. Akhtar, S. DeSouza, M. Griffiths

O83

St.Andrews Burns Unit Introduction: Under the European Working Time Directive junior doctors

are only permitted to work a 48hr week & 13hrs in each 24hr period. This has led to the introduction of more shift-based work and more patient handovers. Our aim is to see how handovers within England are being performed, if they are meeting BMA standards and as a result patient care suffering? Methods: Based upon the BMA guidelines for a good handover a telephone audit was performed of the acute Surgical junior doctors on call. This was performed in three years 2008, 2009 and 2011. Results: 119 hospitals were contacted within 10 deaneries, with a 93 % response rate. Consultant attendance improved from 7.8% to 40.4% (p = 0.03). Handovers lasted on average 22 minutes, however less were happening in working time (p = 0.02). Only 41% reported that their handover time was protected. Having a designated place for handovers improved from 60.8% to 80% (p = 0.04). Handovers were also less likely to be disturbed improving from 61% to 43 %. Quality of Information handed over improved: availability of beds 7.8% to 54%, critically ill patients 86.3% to 87.5% and total patients handed over 77% to 94%. (p = 0.03). Happiness with handovers improved from a 64 % score to 71%. The use of electronic handovers increased from 25% to 44%. Conclusion: We feel that we have demonstrated that despite concerns regarding increased numbers of handovers there has actually been an improvement in the quality of surgical handovers despite the need for them to be carried out in surgeons own time. Take-home message: Despite changes in working hours, surgical handovers in the United Kingdom seem to be improving for the better.

O82 The importance of case selection in the English National Training Programme for laparoscopic colorectal surgery (LAPCO)

Implications of rationing and the European Working Time Directive on aesthetic breast surgery: A study of trainee exposure in 2005 and 2011 N. Mabvuure1,2 , M-J. Hallam2 , S. Lo2 , C. Nduka2 1 Brighton and Sussex Medical School, Brighton, 2 Queen Victoria Hospital, Holtye

Road, East Grinstead Introduction: There are concerns that current trainees may be lacking

operative experience in aesthetic and functional breast operations (AFBOs). This study aimed to compare trends in AFBOs between a single NHS hospital and an associated private hospital. Trainee operative exposures in AFBOs were also examined. Methods: Databases of both hospitals were retrospectively analysed for all AFBOs between 2005 and 2011, noting the total number of cases and grade of the principal surgeon. Results: There was a 55% drop of NHS AFBOs performed in 2011 compared to 2005 (p < 0.0001), matched by a corresponding increase of 57% at the private hospital. Trainees performed proportionally less bilateral breast augmentations in 2011 than in 2005 (29.4% vs. 37.7%, p > 0.05). Trainees performed proportionally more bilateral breast reductions operations in 2011 than they did in 2005 (42.2% vs. 41%, p > 0.05). Proportionally, trainees performed less mastopexies in 2011 than they did in 2005 (32.6% vs. 16.2%, p > 0.05). Conclusion: Current trainees in plastic surgery face a significant reduction in operative exposure to AFBOs compared to their predecessors due to the EWTD working hours, surgical rationing policies, and an increasingly consultant led service. Partnerships with the private sector may be required to increase exposure. Take-home message: Future plastic surgery consultants might have limited experience in aesthetic and functional breast operations. This is likely to affect both the NHS and private sectors and therefore, both sectors are encouraged to form partnerships to increase trainee exposure to these operations.

H. Mackenzie1 , D. Miskovic1 , M. Ni1 , M. Coleman2 , G. Hanna1 1 Imperial College, London, 2 Derreford Hospital, Portsmouth

Introduction: Case selection has been shown to influence patient morbidity

and mortality during self-taught training in laparoscopic colorectal surgery. This study aims to identify the impact of case selection on training quality


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O84 The acquisition and retention of complex clinical procedural skills amongst medical students – teaching method or student traits? D. P. Mitchell, P. S. Waters, G. Flaherty, B. Kelly, D. Devitt, M. J. Kerin Discipline of Surgery, Clinical Science Institute, University College Hospital, Galway, Ireland Introduction: The acquisition of clinical skills is an essential component

of learning for medical trainees. The objective of this study was to assess which teaching method of performing urinary catheterisation is associated with most efficient skill acquisition and retention. We evaluated factors affecting acquisition and retention of skills when using simulators as adjuncts to medical training. Methods: Forty-two second year medical students were taught urinary catheter insertion using different teaching methods. The interactive group (n = 19) were taught using a PowerPoint presentation and a high fidelity human urinary catheter simulator. They were provided with the use of simulators prior to examination. The observer group (n = 12) were taught using the same method but without with simulator use prior to examination. The didactic group (n = 11) were taught using PowerPoint alone. Student characteristics such as hand dexterity and IQ were measured to assess intrinsic differences. All students were examined at four weeks to measure retention. Results: Catheter scores were significantly higher in the interactive group (p < 0.005). Confidence scores with catheter insertion were significantly lower in the didactic group at the retention test (p < 0.05). Retention scores were higher in the interactive group (p < 0.001). A significant positive correlation was observed between laparoscopy scores, time to completion with overall catheter score (p < 0.05).Teaching method, spatial awareness and time to completion of laparoscopy were significantly associated with higher catheter scores (p = 0.001).Retention scores at 4 weeks were significantly associated with teaching method and original catheter score (p = 0.001). Conclusion: The importance of simulators in teaching a complex procedural skill has been highlighted. Didactic teaching method was associated with a significantly higher rate of learning decay. Take-home message: Simulation is critical for successful skill transfer and retention.

ORAL PRESENTATIONS 2B VASCULAR 1

O85 TIE2-expressing monocytes are key regulators of revascularisation in the ischaemic limb A. S. Patel1 , A. Smith1 , S. Nucera2 , F. Pucci2 , P. Saha1 , J. Humphries1 , K. Mattock1 , R. Q. Attia1 , S. Grover1 , O. T. A. Lyons1 , S. Egginton3 , R. Siow1 , A. Ivetic1 , M. Waltham1 , M. De Palma2 , B. Modarai1 1 Academic Department of Surgery, Cardiovascular Division, King’s College London

and the Biomedical Research Centre at Guy’s & St Thomas’ NHS Foundation Trust and King’s College London. 2 San Raffaele-Telethon Institute for Gene Therapy, Milan, 3 University of Birmingham Medical School Introduction: We have previously shown that the numbers of angiogenic

TIE2-expressing monocytes (TEMs) are higher in the circulation and muscle of patients with critical limb ischaemia (CLI). We aimed to determine the role of these cells in revascularising muscle using an experimental model of limb ischaemia. Methods: Temporal changes in circulating TEMs were measured by FACS analysis in a murine model of hindlimb ischaemia (HLI, n = 5/timepoint). Hindlimb perfusion was measured by laser Doppler (n = 9/group) after (i)gene silencing of TIE2 expression on circulating TEMs using a novel microRNAbased double lentiviral system; (ii)injection into the ischaemic hindlimb of either


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murine monocytes transduced ex-vivo with Tie2 lentivirus or FACS-sorted TEMs from CLI patients. Results: Similar to our findings in CLI, there was over three-fold increase in circulating TEMs following HLI compared with sham controls (P < 0.0001,ANOVA). TIE2-expressing macrophage numbers were also raised in the ischaemic hindlimb (P < 0.05). Tie2 silencing halved the rate of neovascularisation in the ischaemic hindlimb (P < 0.0001) while injection of Tie2 over-expressing murine monocytes or human TEMs approximately doubled the recovery of perfusion (P < 0.001). Human TEMs prevented limb loss in 80% of mice, compared with only 20% treated with TIE2-ve monocytes and none in limbs injected with vehicle control. Conclusions: TEMs are mobilised following ischaemia. Manipulating their numbers alters the recovery of perfusion in the ischaemic muscle, suggesting an important role for these cells in revascularisation of the limb. Clinical studies will show whether delivery of TEMs represents a novel angiogenic cell therapy for the salvage of critically ischaemic limbs in patients not amenable to conventional treatments. Take-home message: TIE2-expressing monocytes play a key role in regulating revascularisation of the ischaemic limb. These cells represent a novel therapeutic target for the treatment of patients with unreconstructable critical limb ischaemia.

O86 Predicting carotid artery disease and plaque vulnerability from cellderived microparticles: The carotid artery biomarker study A. Wekesa1 , K. S. Cross2,3 , J. Dowdall2,3 , H. Prins3,5 , J. Phelan1 , O. O’Donovan1 , R. Landers2,3 , M. Doyle2 , O. O’Brien2 , L. Byrne4 , M. Harrison1 1 Waterford Institute of Technology, Waterford, Ireland, 2 Waterford Regional Hospital, Waterford, Ireland, 3 Royal College of Surgeons, Dublin, 4 Adelaide and Meath Hospital, Dublin, 5 Connolly Hospital, Dublin, Ireland

Introduction: Cell-derived microparticles (microparticles) are small plasma membrane derived vesicles ( 25] had elevated neutrophils [13.6 vs 7.4, p < 0.001] and monocytes [0.89 vs 0.6, p = 0.02] on admission compared with controls. Moderately shocked patients [BD 2.1-6] demonstrated higher neutrophil counts compared to the control group [13.7 vs 7.4, p < 0.001]. Severely shocked patients [BD > 6] demonstrated elevated lymphocyte counts [3.2 vs 2.0, p = 0.001]. Neutrophil counts were higher in patients who developed infections during admission [13.1 vs 10.1, p < 0.001] and in patients who developed MODS [2.8 vs 10.9, p = 0.02]. Median Length of Stay (LOS) was greater in patients with elevated neutrophils compared to patients with normal counts [16d vs 3d]. There was no significant relationship with 28-day mortality for any of the cell lines, although a trend towards higher monocyte counts in survivors was observed [0.88 vs 0.75, p = 0.07]. Conclusion: Shock and tissue injury lead to derangements in DWCC at admission. Elevated neutrophils were associated with increased LOS, infectious episodes and MODS. Further investigation is required to delineate the functional role of individual white cell populations in trauma. (ISS, Injury Severity Score; BD, Base Deficit) Take-home message: There are specific patterns of admission differential white cell counts in patients with injury and traumatic shock. Elevated neutrophil count on admission is associated with increased length of stay, infections and multi-organ dysfunction.

O95

O96 Meniscal repair surgery; Significance of early and simultaneous ACL reconstruction on healing of meniscal repair H. Majeed, K. V. Sigamoney, S. V. Karuppiah, G. Geutjens, R. Straw Royal Derby Hospital Introduction: Meniscal injury is currently a well-recognized source of knee

dysfunction. It would be ideal to repair all meniscus tears; however, the failure rate is significantly high, but may be reduced by careful selection of the patients. OBJECTIVES: The objective of our study was to assess the role of ACL reconstruction on the outcome of meniscal repair. Methods: Retrospectively, all consecutive patients between Jan 2008 to Dec 2010, who underwent meniscal repair, were included. Patients’ notes were reviewed and details of type of tear, chronicity, location and surgical details were reviewed. We used ‘symptomatic resolution’ as the outcome measure. Results: 136 meniscal repairs were performed in 122 patients with mean age of 26.8 years. Mean follow up duration was 9 months. Ligament injuries were found in 61% patients (n = 83). Patients who had ACL reconstruction performed early and along with meniscal repair (n = 55), had failure of meniscal repairs in 14.5% (n = 12) cases. Patients who had delayed ACL reconstruction (after 6 weeks of an initial meniscal repair, n = 26), had failure of meniscal repair in 27% (n = 22) cases (p value = 0.0006). 63% patients had medial and 37% had lateral meniscal repairs performed, with failure rate of 19% for medial and 12% for lateral menisci. Conclusion: The success rate of meniscal repair was found to be significantly better if simultaneous and early ACL reconstructions (within 6 weeks) were performed along with meniscal repair. Take-home message: The outcome of meniscal repair is better if simultaneous and early ACL reconstructions (within 6 weeks) were performed along with meniscal repair.

The incidence of calcified atherosclerosis and association with in-hospital mortality in trauma

O97

K. Oakland, H. De’Ath, K. Brohi Royal London Hospital, Barts Health NHS Trust Introduction: Studies have revealed that older trauma patients have higher

mortality. Arterial calcification on computerized tomography (CT) as a marker of cardiovascular disease is predictive of poor outcome in many disease states. The aim of this study was to establish the incidence of arterial calcification in trauma and to investigate any association with mortality. Methods: A single centre retrospective cohort study of trauma patients aged >45 years, presenting to a trauma centre between 1st January 2009 and 31st October 2011. The presence of calcified atherosclerosis in the aorta, visceral arteries and common iliacs was determined on admission CT scans of the chest, abdomen and pelvis. Multivariate logistic regression was used to determine the association with in-hospital mortality. Results: Five hundred and ninety one patients were included. The median age was 56, 81% were male and 93% suffered blunt trauma. Fifty (8.46%) patients died during admission. Calcification of extra-coronary arteries was common, present on 472 (79.86%) scans. The common iliac arteries were the most commonly calcified individual arterial bed, found on 372 (62.94%) scans. When controlled for age, sex and injury severity score, superior mesenteric artery and


When sheep play tennis Z. Ahmad, R. Brooks, F. Henson, J. Wardale, M. Abdus-Samee, A. Noorani, G. Tytherleigh-Strong, N. Rushton University of Cambridge Introduction: Rotator cuff tears remain a problem, with massive tears having

a failure rate of repair reported of up to 60%, despite advances in surgical techniques. Tissue engineering techniques offers the possibility of regenerating damaged tendon tissue to a pre-injury state. We explore these techniques by implanting two novel tendon augmentation grafts with use of platelet rich plasma (PRP) in sheep. Methods: A total of 24 sheep were operated on, with the infraspinatus being surgically cut from its attachment to the humeral head. Each tendon was repaired using suture anchors and an interpositional implant according to 4 groups: (1) Empty control, (2) Novel collagen fibre implant with PRP (3) A novel collagen sponge implant (4) and the collagen sponge with PRP. The sheep were killed at 12 weeks and the implant site harvested and its histology evaluated.

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Results: Our findings showed that these novel grafts were well integrated

into the tissue, with minimal inflammatory response. However, as expected, the material had not yet completely broken down. Our initial findings suggest that the combination of PRP with the collagen sponge best enhanced the repair of the tendon. Conclusion: Tissue engineered collagen grafts hold great potential for the repair of tendons. Take-home message: Tissue engineered collagen grafts hold great potential for the repair of tendons.

O98 Unilateral lower limb loss following combat injury – medium term outcomes in british military amputees P. M. Bennett1 , I. D. Sargeant1 , M. Midwinter1,3 , J. G. Penn-Barwell1,2,3 1 Academic Department of Military Surgery and Trauma, Royal Centre for Defence Medicine, Birmingham , 2 Institute of Naval Medicine, Gosport, 3 National Institute for

Health Research (NIHR), Surgical Reconstruction and Microbiology Research Centre (SRMRC), Birmingham Introduction: Modern high-energy military weapons produce devastating and

often life-changing injuries. This study presents the injuries, surgical treatment and outcomes of British service personnel who sustained a primary unilateral lower limb amputation following combat injury over 6 years. Methods: All cases of unilateral lower limb amputation sustained between 2004 and 2010 were identified from the UK military Joint Theatre Trauma Registry (JTTR). Cases were excluded if they involved amputation at the ankle or more distally, or were delayed amputation following failed limb salvage. Data was collected from JTTR, clinical records and patients contacted and asked to complete an SF-36 questionnaire. Results: Forty-eight patients sustained a primary unilateral lower limb amputation. Twenty-one had a trans-tibial amputation, 9 a knee-disarticulation and 18 a trans-femoral amputation. Full outcome data was available for 39 patients (81%). The minimum follow-up was 25 months (mean 39 months, SD 16, range 25–76). The average age of patients was 24 (SD 5.1): all were injured by blast weapons. The mean NISS was 27 (median 24, range 9–75, SD 14) and the median number of procedures per residual limb was 4. The physical component score (PCS) of the SF-36 measure declined significantly with more proximal amputation level (p = 0.102 Kruskall-Wallis). Mental component scores (MCS) did not vary between amputation levels (p = 0.114). Pain (p = 0.332), prosthesis use (p = 0.503), re-admission (p = 0.228) and mobility (p = 0.087) did not vary between amputation heights either. Conclusions: These findings demonstrate that quality of life is improved with a longer residual limb, and support surgical attempts to maximise residual limb length. Take-home message: Military patients sustaining a primary unilateral lower-limb amputation have a significantly higher quality of life with longer residual limbs. Stump length should be preserved at all costs.

O99 A 100 year review of blood use in civilian mass casualty events – how best to predict future needs S. M. Glasgow, Z. B. Perkins, R. Davenport, N. R. M. Tai, K. Brohi

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and ISS > 15) were stratified against blood products (RBCs, FFP, platelets and cryoprecipitate) initially required following events. Results: 51 MCEs involving 11,821 casualties were included in the study. RBC data was available for all events; mean use was 68U per event (range 6-596U) and 62-74% of total demand was utilized within the first four hours. The mean ratio of RBCs to FFP, platelets and cryoprecipitate was 1:3:4:6 respectively. Events involving a related mechanism of injury (terrorist events) showed a strong correlation (R2 value 0.75, p = 0.01) between RBC use and number of ISS > 15 casualties with mean RBC use of 5.9U (range 1.9-13.0U) per ISS > 15 casualty. Conclusions: DCR requires much greater volumes of FFP, platelets and cryoprecipitate than required previously, planning for which could be based on RBC needs. Prediction of future MCE RBC need can best be achieved through expected number of ISS > 15 casualties, representing a useful planning tool to help reduce critical mortality from these events. Abbreviations: MCE, Mass casualty event; DCR, Damage control resuscitation; RBC, Red blood cell; ISS, Injury severity score; FFP, Fresh frozen plasma. Take-home message: Blood planning for DCR in MCE is vital to reduce critical mortality in these resource constrained environments. Number of ISS > 15 patients correlates well with RBC need and offers a potential planning tool for future blood needs.

O100 Identifying and addressing preventable process errors in trauma P. H. Pucher, R. Aggarwal, A. Twaij, N. Batrick, M. Jenkins, A. Darzi Imperial College London Introduction: Management of the acute trauma patient is complex, with

potential for error and adverse events. Avoidable injuries and deaths are not well understood. The application of error analysis may aid in greater understanding of root causes and guide future development of error reduction strategies and has not previously been attempted. Methods: Weekly case review meetings for a designated Trauma Centre were retrospectively reviewed over one year. Errors were identified and corroborated with casenote review by a reviewer blinded to any identified events. All events were classified according to the Joint Commission on Accreditation of Healthcare Organisations taxonomy and typified as structural or process errors, and omission or commission errors. Results: 1,752 major trauma patients were admitted over the study period. 169 preventable errors were identified through analysis of case review meetings and casenote review. Clear patient harm was identified in 3.3% of cases, with risk of harm in 26%. More commonly, errors resulted in delays (44%). Most errors occurred during the initial phase of care in the emergency department (53%). The majority were identified as process errors (88%), with 62% of these considered errors of omission rather than commission. Conclusion: This study reports error incidence in trauma and typifies according to type and root cause. It identifies errors of omission in particular as the most common recurring events. Modern error theory allows the identification of the most effective strategies for future error reduction, as a result, which may improve future care and outcomes in trauma. Take-home message: Through the application of modern error theory we have been for the first time able to identify common patterns of error in trauma as well as interventions to reduce them. Whilst the provision of resources and structural factors are important, this study suggests that protocols to reduce process error may be more effective still.

Department of Trauma Sciences, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London Introduction: MCEs generate critically injured patients in which haemorrhage

is a leading preventable cause of death. Victims require DCR with blood and high dose coagulation therapy in a resource limited environment. Our objective was to review blood use in MCEs and assess available casualty profiles as a tool for predicting future blood needs. Methods: A 100 year retrospective literature review of worldwide civilian MCEs was performed. Casualty profiles (number: injured, hospitalized, admitted


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was a similar incidence of acute rejection in both groups (EVNP 22.4% vs CS 26.4%; P = 1.000). Conclusion: This first series of EVNP in marginal donor kidneys suggests that this technique of restoring circulation and function prior to transplantation is a safe and feasible method of preservation.

ORAL PRESENTATIONS 3A TRANSPLANTATION

O101 O103

The utility of time-zero biopsy scoring of ischaemia/reperfusion injury after liver transplantation

How helpful are serum markers in evaluating graft pancreatitis following simultaneous pancreas kidney transplantation?

J. Ali, S. Harper, S. Mir, J. Klink, A. Bradley, G. Pettigrew University of Cambridge Introduction: The utility of time-zero biopsies after orthotopic liver

transplantation (OLT) remains unclear. The aim of this study is to evaluate histological grade of ischaemia/reperfusion injury (IRI) on time-zero biopsy as a prognostic indicator following OLT. Methods: Between October 1996 and February 2010, 883 OLT were performed at our centre. Time-zero biopsies were available for 572 patients. Patients were divided into four groups based on histological grade of IRI: nil (121), mild (303), moderate (124) and severe (24) and clinical data compared for each. Results: Biopsy score severity was strongly associated with recognised risk factors for IRI, including donation after cardiac death, donor age, donor BMI and allograft steatosis (p < 0.001). Higher IRI grades also correlated closely with the incidence of post-perfusion hyperkalaemia (p = 0.001) Interestingly, neither cold nor warm ischaemic times were significantly different between the groups (p = 0.5). The degree of IRI on biopsy correlated closely with graft outcome. In particular, a severe IRI grade was associated with significantly greater post–transplant morbidity compared to the other 3 groups. The severe group demonstrated markedly higher rates of primary non-function (13% vs 6%; p = 0.02), early graft dysfunction (57% vs 32% p < 0.0001) and the need for re-transplantation within 90 days (13% vs 2%; p = 0.01). One year graft survival in nil, mild and moderate groups were significantly better than in the severe group (82%, 85%, 90% and 61% respectively; p = 0.003). Conclusion: Time-zero biopsies have value in predicting adverse clinical outcomes following OLT and allow identification of patients at risk of a complicated post-operative course. Take-home message: Assessment of ischaemia reperfusion injury on time zero biopy after liver transplantation is an accurate prognostic indicator of post-operative outcome.

M. Chhabra, F. Powell , N. Hilliard, J. Bradley, C. Watson, A. Shaw, S. Harper, G. Pettigrew University of Cambridge Introduction: Graft pancreatitis, with or without underlying acute rejection,

O102

remains difficult to diagnose using clinical assessment alone, leading to indiscriminate use of cross-sectional imaging. The aim of this study is to evaluate the accuracy of routine serum markers in predicting allograft inflammation following simultaneous pancreas-kidney transplantation (SPK). Methods: A retrospective analysis of 109 SPK performed at our centre between January 2005 and December 2010 was undertaken. All 299 post-operative CT scans performed in this period were blindly assessed by 2 radiologists for features of pancreatitis: graft enlargement (normal/enlarged), graft perfusion (normal/heterogenous), ascites (absent/present) and peri-pancreatic fat changes (mild/moderate/severe). Serum markers measured at the time of each scan were recorded to assess correlation with radiological severity of pancreatitis. Results: Serum C-reactive protein (CRP) levels correlated closely with radiological evidence of graft pancreatitis. Mean CRP levels were significantly higher in patients with CT findings suggestive of graft pancreatitis, including enlarged vs. normal graft size (114+/−74 vs. 76+/−80 mg/dL), heterogenous vs. normal perfusion (132+/−81 vs. 82+/−76 mg/dL), presence vs. absence of ascites (125+/−81 vs. 74+/−73 mg/dL) and mild vs. moderate vs. severe peripancreatic fat changes (23+/−34 vs. 53+/−59 vs. 107+/−80 mg/dL). Mean white cell counts were also significantly higher in patients with enlarged grafts (10+/−5.1 vs. 8.7+/−5.5) and ascites (11+/−5.2 vs. 8.7+/−5.6). In contrast, neither serum amylase nor lipase had any correlation with radiological grading of pancreatitis. Conclusion: CRP and white cell count appear to reflect pancreas graft inflammation and may be useful in diagnosing graft pancreatitis and avoiding overuse of radiological investigations. Take-home message: CRP and white cell count are useful markers of graft pancreatitis and as such may allow avoidance of repeated radiological investigations to assess graft inflammation.

The first clinical series of ex-vivo normothermic perfusion (EVNP) in marginal donor kidney transplantation

O104

S. A. Hosgood, C. Crotty, M. L. Nicholson University of Leicester Introduction: Ex-vivo normothermic perfusion (EVNP) is a novel method of

preservation that restores circulation and allows an organ to regain function prior to transplantation. The aim of this study was assess the effect of EVNP in kidneys from marginal donors. Methods: Twenty two kidneys from marginal donors underwent a short period of EVNP immediately before transplantation. Kidneys were perfused with a plasma free red cell based solution at a mean temperature of 34.7◦ C. The outcome of these kidneys was compared to a control group of 53 marginal donor kidneys that underwent static cold storage (CS). Results: The average donor age was 57 ± 11.7yr in the EVNP and 60 ± 9.5yr in the CS group (p = 0.335). EVNP kidneys were perfused for an average of 63.2 ± 14.2min, all produced urine and were transplanted successfully. The total cold ischaemic time was 12.6 ± 4.6h in the EVNP group and 11.8 ± 3.7h in the CS group (P = 0.918). The delayed graft function rate (DGF) defined as the requirement for dialysis within the first 7 days was 1/ 22 patients (4.8%) in the EVNP group versus 18/53 (33.9%) in the CS group (P = 0.008). There was no difference in graft or patient survival at 12 months (P = 0.510, 1.000). There


Significant response to local ablative bridging treatments facilitates acceptable rates of survival following liver transplantation for HCC R. Lochan1,3 , A. Vallance1,3 , J. J. French1,3 , B. C. Jaques1,3 , H. L. Reeves2,3 , R. M. Charnley1 , S. A. White1,3 D. M. Manas1,3 1 Department of HPB Surgery, 2 Hepatology & 3 Transplantation, Freeman Hospital

Introduction: Liver Transplantation (LT) is a well-recognised treatment

option for selected patients with hepatocellular carcinoma (HCC). However there is concern regarding tumour progression whilst on the waiting list. UK guidelines recommend local ablative therapy for all HCC patients being considered for LT. Methods: All consecutive patients with HCC who have undergone LT between 2001–10 were identified from our prospectively maintained database. All patients are discussed at LT assessment meeting and at a separate HPB MDT for consideration of bridging treatment [trans-arterial chemo-embolisation (TACE) and/or radio frequency ablation (RFA)] whilst on the waiting list. We have sought to evaluate the benefits of this.

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Results: 55 HCC patients underwent LT (M:F = 43:12 ). Bridging treatments were TACE n = 31, RFA n = 28, or both n = 4. Six patients did not undergo any

form of bridging treatment as they rapidly progressed to LT. The response to bridging treatment was complete (n = 8), good (n = 10), moderate (n = 18), poor (n = 4) or no response (n = 15). There were 2 deaths within 100 post-operative days. At last follow-up n = 21 were disease free. Overall survival [median (95% CI)] was 62 (53–71) months [good response to bridging treatments it was 67 (55 – 79) months and those with poor/no response it was 53 (42 – 64) months (log-rank p = 0.059)]. Conclusion: This study demonstrates the feasibility of various bridging treatments for patients with HCC who await liver transplantation in the UK. In combination with careful patient selection and surveillance acceptable rates of survival can be achieved. Take-home message: Bridging treatments for HCC are feasible and response to bridging treatment suggests improved survival following liver transplantation.

O105 What are the implications of 12-month surveillance biopsies following renal transplantation? J. P. Hunter, V. Hansrani, R. Babla; M. L. Nicholson Transplant Group, University of Leicester Introduction: Surveillance biopsies are performed in renal transplant patients

with stable renal function at set times following transplantation. Biopsies are performed to detect sub-clinical rejection (SCR), which is evidence of inflammation with no change in renal function. Surveillance biopsies are not routinely performed in all centres. We reviewed our 12-month surveillance biopsies and their impact on patient management. Methods: A retrospective review of patients who underwent a kidney transplant between 2008 and 2011 was performed. Data were collected from patient case notes, histology reports and clinical databases. Patients who underwent a 12-month surveillance biopsy were included. Exclusions included clinical trial patients and those undergoing diagnostic biopsies. Histology was scored according to Banff classification and chronic damage was classed as mild, moderate or severe. Results: Ninety-six patients had a 12-month biopsy and 81 were included for analysis. 44 were living donor and 37 were cadaveric transplants. Eleven (14%) biopsies showed normal kidney. Thirty-six biopsies (44%) showed chronic damage, in 9 cases it was severe and 3 had immunosuppression altered. In total 14 (17%) patients had medication altered of whom 3 (4%) were admitted for intravenous methylprednisolone. SCR was found in 2 of these 3 patients. Only 4 of 17 patients with Banff borderline rejection had medications altered. There were no adverse events requiring hospital admission. Conclusion: Twelve-month surveillance biopsies have an impact on immunosuppressive therapy and patient management and SCR is an important finding resulting in admission for treatment. Take-home message: Surveillance biopsies are safe and help direct immunosuppressive therapy in renal transplant recipients

O106 Mice on trial: Is xenografts using human tissue a better model of cancer than xenografts formed from cell lines? G. Sadadcharam1 , M. McCourt2 , C. Ryan3 , K. O’Connor3 , B. Bennett3 , D. G. Power4 , S. O’Reilly4 , J. H. Wang1 , H. P. Redmond1 , E. J. Andrews1 1 Department of Academic Surgery, Cork University Hospital, Ireland, 2 Department of Colorectal Surgery, Cork University Hospital, Ireland, 3 Department of Histopathology,

Cork University Hospital, Ireland, 4 Department of Medical Oncology, Cork University Hospital, Ireland Introduction: Xenograft tumours are validated models using either patient

samples (primary xenografts) or cell lines (secondary xenografts) grown in a murine host. Repeated culturing of cancer cell lines results in epigenetic changes


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and subsequent behaviour changes distinct from primary human cancers. The aim of this study is to form both models and compare their responses to chemobiologic therapy. Methods: Fresh primary colorectal adenocarcinoma tissue or colorectal cell lines (SW480 non metastatic line / SW620 metastatic line) were inoculated subcutaneously into immunodeficient mice to form primary and secondary xenografts respectively. Both models were subjected to either a 5-fluorouracil (5-FU) or Irinotecan trial. The clinical response and biological features were evaluated. Results: Secondary xenografts were more aggressive with a shorter time to tumour formation, higher uptake rate and more aggressive histological features compared to primary xenografts. The mice were randomised to either the control group (saline) or to the treatment group [60 mg/kg of 5FU (SW620/primary xenografts) or 60 mg/kg of Irinotecan (SW480/ primary xenografts)] via intraperitoneal injection. In the 5FU group, the primary xenografts began regressing after Day 2 but the secondary xenografts continued to grow until Day 8. The decrease from the maximal tumor volume to the study end point was evaluated with primary xenografts showing a greater decrease compared to secondary xenografts (56.6% vs. 10.4%; p = 0.002). Conclusions: Primary xenografts are a better model for the in vivo testing of new chemobiological agents and allows for drug screening in order to personalise an individual’s chemotherapy regime. Take-home message: We demonstrate for the first time the ability to grow tumours in mice from fresh human colonic adenicarcinomas. Tumours formed in mice from patient derived adenocarcinomas produce more clinically accurate testing than tumours formed from cell lines.

O107 Withdrawn

O108 Tissue engineering of the kidney using a whole organ decellularisation approach M. He1 , A. Callanan1,2 , C. Chiappini1 , M. M. Stevens1 1 Imperial College London, 2 University of Limerick

Introduction: Renal transplantation is the optimal form of renal replacement

therapy. However, it is restricted by the limited pool of organs available from cadaveric donors – over 2500 renal transplants were performed in 2010 but there are more than 50,000 patients with end stage renal failure in the UK. Objective: To use a new approach in tissue engineering – ‘whole organ’ decellularisation’ – to produce a complete kidney extracellular matrix (ECM) scaffold and recellularised organ construct. This approach has been successfully utilised in the heart, lungs and liver in animal studies. Methods: Wistar rat whole kidneys were decellularised with 1% w/v SDS. Characterisation of decellularisation included histology (H+E), immunohistochemistry (IHC) for ECM components, vascular corrosion resin casting (Batson’s no. 17 kit). Recellularisation with i) rat primary renal cells and ii) rat bone-derived mesenchymal stem cells were performed within a bioreactor for 7 days. Recellularisation viability was assessed with LIVE/DEAD staining and Alamar blue assay; characterisation of constructs by histology, IHC for renal cell markers and scanning electron microscopy. Results: Rat kidneys were successfully decellularised to create whole kidney ECM bio-scaffolds. Characterisation of the bio-scaffold demonstrates good decellularisation, preservation of ECM components and architecture, renalspecific architecture and preservation of the vasculature. Recellularisation studies show penetration and distribution of viable cells throughout the bio-scaffold architecture within ‘renal-like’ structures, suggesting an appropriate response to structural and bio-inductive cues within the bio-scaffold.

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Conclusion: Successful decellularisation of rat whole kidneys with recellular-

isation studies on this bio-scaffold have shown formation of cellular ‘renal-like’ structures within the matrix architecture. Take-home message: Tissue engineering using decellularised whole organ ECM bio-scaffolds (e.g. in the kidney) may provide a strategy to create an alternative source of organs for transplantation.

O109 The effects of arterial pressure during a period of ex-vivo normothermic perfusion in a porcine kidney model M. Patel, S. A. Hosgood, C. Hyde, M. L. Nicholson University of Leicester Introduction: Ex-vivo Normothermic Perfusion (NP) is a novel method of

kidney preservation. However, there is a risk that higher perfusion pressures may cause endothelial injury. The aim of this study was to evaluate the effects of two different arterial pressures during NP. Methods: Porcine kidneys underwent static cold storage (CS) for 23 hours followed by 1h of ex-vivo NP using leukocyte depleted blood at a mean arterial pressure of either 55 or 75 mmHg. Following this, kidneys were reperfused for 3h to assess renal function and injury. This was compared to a control group that underwent 24h CS. Results: During NP kidneys perfused at 75 mmHg had a higher renal blood flow (RBF), increased oxygen consumption (55 ± 17 vs 30 ± 16 ml/min/g; P = 0.026) and produced more urine (P = 0.002) than kidneys perfused at 55 mmHg. During reperfusion, RBF was significantly higher in the 75 mmHg group compared to the control (AUC 75 mmHg 447 ± 187, 55 mmHg 520 ± 243 vs control 285 ± 82 ml/min/100g.h P = 0.040). There was no significant difference in renal function between the groups however tubular injury was significantly reduced in the 75 mmHg kidneys (P = 0.007). The 55 mmHg group kidneys produced significantly less urine compared to the 75 mmHg and control (P = 0.016). There was no significant increase in levels of endothelin-1 in the 75 mmHg group (P = 0.190). Conclusion: Kidneys perfused at 75 mmHg during 1h of ex-vivo NP had a higher level of renal metabolism compared to kidneys perfused at 55 mmHg. 75 mmHg is a more favourable arterial pressure with improved haemodynamics, less tubular damage and no evidence of increased endothelial injury during reperfusion. Take-home message: A perfusion pressure of 75 mmHg appears to be an optimal perfusion pressure for normothermic kidney perfusion.

O110 Transcriptomic changes in human renal biopsies from living and cadaveric donors at 30 minutes and 3 months post-transplantation B. Yang1,2 , N. Sylvius3 , J. Luo4 , C. Yang5 , C. Crotty1 , Z. Da6 , M. L. Nicholson1 1 Transplant Group, Department of Infection, Immunity and Inflammation, University

of Leicester, Leicester General Hospital, University Hospitals of Leicester, United Kingdom, 2 Department of Nephrology, Affiliated Hospital of Nantong University, Nantong 226001, P. R. China, 3 University of Leicester, Genetics, Leicester, United Kingdom, 4 MRC Toxicology Unit, Genomics Group, Leicester, United Kingdom, 5 Department of Urology, Zhongshan Hospital, Fudan University, Shanghai, P. R. China, 6 Department of Rheumatology and Immunology, Affiliated Hospital of Nantong University, Nantong 226001, P. R. China Introduction: Renal allograft survival is >90% at 1 year, but falls dramatically

microarray samples and additional 33 biopsies. Relevant clinical data were analyzed related to gene expression. Results: The overall gene profiles were clearly different in 30-minute and 3-month samples. Differentially expressed genes were 681 at 30 minutes, which reduced to 75 at 3 months (1.5 fold change, p < 0.05) between two donor types with significantly longer warm and cold ischemic time in CAD. Many acute response genes (FGA, VWF, SERPINA1) were up-regulated at 30 minutes, while genes involved in inflammation, nephrotoxicity and proliferation were up-regulated at 3 months. More interestingly, up-regulated tissue remodeling associated genes (COL3A1, TIMP1, MMM9) and down-regulated FGA at 3 months in contrast to 30 minutes in CAD was not seen in LD. A list of 120 genes closely correlated with serum creatinine and fibrosis at not only early times, but also 12 and 24 months. Conclusions: Transcriptomic signatures were shifted from acute responses to tissue damage and remodeling by the time post-transplantation with divergent profiles between LD and CAD. These changed signatures might be linked to initial donor injury and adaptive immune responses, also potential biomarkers for diagnosis and interventions. Take-home message: Transcriptomic signatures were shifted from acute responses to tissue damage and remodeling by the time post-transplantation with divergent profiles between LD and CAD. These changed signatures might be linked to initial donor injury and adaptive immune responses, also potential biomarkers for diagnosis and interventions.

O111 Sildenafil enhances renal blood flow but does not protect against ischaemia reperfusion injury in a model of donation after circulatory death kidney transplantation L. V. Randle2 , S. A. Hosgood1 , M. Patel1 , J. A. Bradley2 , C. J. Watson2 , M. L. Nicholson1 1 University of Leicester, 2 University of Cambridge

Introduction: Sildenafil has been used as a pre-conditioning agent to protect

against ischaemic injury, although there is little evidence for its benefit in reducing ischaemia reperfusion (I/R) injury in renal transplantation. The aim of this study was to assess the effects of sildenafil on I/R injury in a porcine model of donation after circulatory death (DCD) kidneys. Methods: Kidneys were subjected to 20 minutes warm ischaemia followed by 18 hours cold storage. After preservation kidneys were reperfused on an ex vivo perfusion system for 3 hours with an oxygenated blood based solution. Kidneys were treated with 0.2 mg (n = 4), 0.7 mg (n = 4) or 1.4 mg (n = 6) or no (control, n = 6) sildenafil during reperfusion. Renal function and renal injury markers were measured throughout reperfusion. Results: Renal blood flow was increased in a dose dependent manner with a significantly higher flow in the 1.4 mg treated kidneys compared to the controls [mean area under curve (AUC), (1.4 mg) 482 ± 99, (0.7 mg) 469 ± 123, (0.2 mg) 387 ± 115, (Control) 360 ± 47ml/min/100g.h; P = 0.021]. There was no significant improvement in renal function [AUC creatinine clearance; (1.4 mg) 2.9 ± 0.8, (0.7 mg) 2.5 ± 0.6, (0.2 mg) 3.0 ± 2, (control) 4.5 ± 2.0ml/min/100g.h; P = 0.099], tubular injury [neutrophil gelatinaseassociated lipocalin (NGAL); P = 0.060], levels of inflammatory cytokines (IL-6; P = 0.357, TNFα; P = 0.340) or neutrophil infiltration (P = 0.106) between the groups. Conclusion: Sildenafil had a vasodilatory action but did not affect recovery of renal function or protect against I/R injury. This suggests that sildenafil is not renal protective during the early reperfusion phase in an ex vivo DCD model. Take-home message: Sildenfil has a vasodilatory action during reperfusion but does not protect against ischaemia reperfusion injury.

in 10 years, with no single conventional method allowing timely assessment. To develop novel biomarkers, transcriptomic signatures in human transplant kidneys were investigated. Methods: Renal biopsies from living donors (LD) and cadaveric donors (CAD) at 30 minutes and 3 months post-transplantation (n = 6) were used for wholegeneome profiling. Selected genes were validated by quantitative PCR in 24


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O112 LHBP in preservation solution and autologous blood perfusate protects isolated ischemic porcine kidneys C. Yang3,4 , B. Yang1,2,* , S. A. Hosgood1 , C. Hyde1 , P. Meeta1 , Y. Long5 , T. Zhu3,4 , M. L. Nicholson1 1 Transplant Group, Department of Infection, Immunity and Inflammation, University

of Leicester, Leicester General Hospital, University Hospitals of Leicester, United Kingdom, 2 Department of Nephrology, Affiliated Hospital of Nantong University, Nantong 226001, P. R. China, 3 Department of Urology, Zhongshan Hospital, Fudan University, Shanghai, P. R. China, 4 Shanghai Key Laboratory of Organ Transplantation, Shanghai, P. R. China, 5 Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, P. R. China Introduction: There is an imperative need to develop new approaches to

prevent ischemia reperfusion injury during organ cold storage and reperfusion. A novel levorotatory and cyclic helix B peptide (LHBP) derived from erythropoietin was synthesized recently and its tissue protective roles were evaluated in an isolated ischemic porcine kidney model. Methods: Porcine kidneys subjected to 20 minutes warm ischemia were retrieved and flushed with 500 ml hyperosmolar citrate and cold preserved for 18 hours with or without 10.56 nmol/L LHBP. The kidneys were then reperfused with oxygenated autologous blood with or without LHBP for 3 hours on an isolated organ perfusion system to assess renal function, histology, apoptosis and inflammation. Results: LHBP significantly increased renal blood flow during 2 to 3-hour reperfusion, with increased oxygen consumption and urine output, but decreased serum potassium. The 32 kD precursor of caspase-3, as well as 12 and 17 kD active subunits were all down-regulated by LHBP in after 3-hour reperfusion, while only the 12 kD subunit was decreased post CS. In addition, apoptotic cells were significantly decreased in tubular areas, but increased in lumens and interstitial areas in post CS and reperfusion kidneys. HSP70 was upregulated; myeloperoxidase+ cells was reduced and renal tissue damage was also ameliorated by LHBP. Conclusions: The administration of LHBP during cold preservation as well as hemoreperfusion improved IRI with better renal blood flow, oxygenation, tubular function and renal tissue damage, which might be due to highly expressed HSP70, but less caspase-3 protein, apoptosis in tubular areas and inflammation. Take-home message: The administration of LHBP during cold preservation and hemoreperfusion improved IRI, which might be due to highly expressed HSP70, but less caspase-3 protein, as well as apoptosis and inflammation.

ORAL PRESENTATIONS 3B MISCELLANEOUS 1

O113 Metabolic consequences following colectomy in patients with familial adenomatous polyposis S. Mallappa1 , M. Samarasinghe1 , S. Gabe1 , R. Phillips1 , S. Clark1 , M. Robertson2 1 St Mark’s Hospital, Harrow, 2 University of Surrey, Guildford

Introduction: There is increasing evidence that colon is an active metabolic

organ, removal of which leads to sodium and water depletion, chronic activation of renin-angiotensin-aldosterone system (RAAS), hyperaldosteronism and abnormal glucose tolerance. Previous work has studied patients who have undergone colectomy for inflammatory bowel disease. This is the first such study in patients with familial adenomatous polyposis (FAP). Patients with FAP undergo prophylactic colectomy to prevent development of colorectal cancer and so long term metabolic abnormalities resulting from the surgery would be of


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immense clinical interest. We aimed to determine the prevalence of metabolic disturbance in patients with FAP following colectomy. Methods: 20 FAP patients (8 male) who had undergone either colectomy and IRA or RPC at our institution were recruited in a prospective study.In fasted patients, spot urine and blood samples were collected to measure sodium loss and hydration (urine sodium, potassium, creatinine and serum albumin) and RAAS activation (plasma aldosterone). An oral glucose tolerance test was performed to assess glucose tolerance. Health related quality of life was assessed using SF-36(Version2) and FACIT-F(Version4) questionnaires. Results: Median age since primary surgery was 14.5 years. A preliminary analysis of the data found that ten patients (50 per cent) demonstrated fasting hyperaldosteronism(>250 pmol/L). This hyperaldosteronism led to higher urinary losses of potassium (p = 0.03) and creatinine (p = 0.01). Nine patients with hyperaldosteronism also demonstrated abnormal glucose tolerance with lower reported energy levels. Conclusions: Colectomy in FAP patients may result in metabolic disturbances leading to a negative impact on the quality of life. ABBREVIATIONS: IRA-Ileo-rectal anastomosis,RPC-Restorative proctocolectomy,SF36Short Form health survey,FACIT-F-Functional Assessment of Chronic Illness Therapy-Fatigue Take-home message: Colon is an active metabolic organ, removal of which leads to metabolic adaptation of other tissues in the body. Colectomy in FAP patients may result in metabolic disturbances leading to a negative impact on the quality of life.

O114 Effect of local & systemic growth factors on the human osteoblast response to lysophosphatidic acid and vitamin D3 J. Blackburn, J. Mansell Musculoskeletal Research Unit, Avon Orthopaedic Centre Introduction: Surgical revision for failed total joint replacements is staggering at around £300m/yr. Successful osseointegration requires the production of

a mechanically competent collagenous matrix, by human osteoblasts (hOBs), at the implant site. We aim to improve implant longevity through implant surface functionalisation. Lysophosphatidic acid (LPA) is a bioactive lipid which we found to synergistically co-operate with vitamin D3 (D3) to secure hOB maturation. In developing an LPA-functionalised titanium surface for future arthroplasty we need to ascertain how LPA might interact with other growth factors known to target bone. Methods: Cells were co-treated with LPA & D3 with or without oestradiol, PTH or TGFβ. After 3 days cell number, total alkaline phosphatase (ALP), ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) and osteocalcin were quantified. Results: Of the agents tested only TGFβ influenced the expression of hOB proteins; it enhanced LPA & D3-induced ALP but inhibited osteocalcin expression. Addition of Ki11502, an inhibitor of the platelet-derived growth factor receptor, attenuated the increase in ALP to co-treatment with LPA, D3 and TGFβ. Conclusions: Both oestradiol and PTH were without influence on hOB responses to treatment with LPA & D3. Interestingly TGFβ bolstered the maturation of hOBs to LPA and D3 via a mechanism that may involve an autocrine/paracrine PDGF loop. These preliminary findings are encouraging as a titanium surface functionalised with LPA could co-operate with local TGFβ/PDGF to enhance osteoblast maturation and resultant bone matrix accrual. Research is ongoing to evaluate the efficacy of our modified Ti surfaces to secure hOB formation from their stem cell progenitors. Take-home message: These preliminary findings are encouraging as a titanium surface functionalised with LPA could co-operate with local TGFβ/PDGF to enhance osteoblast maturation and resultant bone matrix accrual.

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O115 3D in vitro cancer model: A tissue engineering approach to cancer research T. Magdeldin1 , A. Nyga1 , M. Loizidou1 , U. Cheema1,2 1 University College London, 2 UCL Centre for Nanotechnology and Regenerative

Medicine, Division of Surgery and Interventional Sciences, UCL Institute of Orthopaedics & Musculoskeletal Sciences) London, U.K. Introduction: Pre-clinical cancer research is generally carried out in

2D cell culture or animal models. Although 2D in vitro cultures are controllable, amenable to molecular manipulation and invaluable for mechanistic investigations; they do not accurately represent the complexity of in vivo interactions. We have developed a spatially accurate 3D in vitro model of colorectal cancer bridging the gap between conventional 2D cell culture studies and model organisms. Methods: Using tissue engineering techniques such as plastic compression, colorectal cancer cells (HT29) and collagen type I were used to construct a dense, artificial cancer mass (ACM). To mimic the tumour microenvironment, the ACM was positioned within stromal cell populated uncompressed collagen containing endothelial cells (HUVECs) and fibroblasts (3T3). Characterization studies included investigations of: cell growth (Alamar Blue), the presence of hypoxia, a key feature of solid cancers (O2 probes), cell morphology and immunofluorescence (VEGF). Results: Cell survival within the matrix was characterized up to 21 days. Cancer cells formed cell aggregates similar to tumour spheroids in vivo and invaded outwards from the ACM. O2 levels within the core of the ACM decreased to ∼10 mmHg within 4 hours, compared to 70 mmHg in the surrounding matrix (p < 0.05). Immunofluorescence confirmed VEGF production by cancer cells at the invading edges of the ACM. Conclusions: Our 3D model exhibits fundamental characterstics of the tumour microenvironment (spatial organization of cell types, tumour invasion, hypoxia and VEGF expression) thus demonstrating realistic potential as an alternative to animal testing. The model is currently under development for therapeutic and imaging purposes. Take-home message: 3D in vitro cancer model exhibits fundamental characteristics of the tumour microenvironment such as spatial organization of cell types, tumour invasion, hypoxia and VEGF expression. The model is currently under development for therapeutic and imaging purposes.

O116 Withdrawn

O117 Do distinct gene and protein profiles of cytokines exist in severe sepsis? J. Sarveswaran, N. Orsi, M. Cummings, S. Homer-Vanniasinkam, D. Burke

Results: Samples were obtained from seventeen controls and sixty patients, of whom 27 died within 28 days. The groups were age and sex matched. 80% of pro-inflammatory and 20% of anti-inflammatory cytokine protein levels were significantly elevated in severe sepsis compared to controls (p < 0.001). An anti-inflammatory cytokine IL-10(15 fold), and two pro-inflammatory cytokines IL-15(2 fold), IL-18(15 fold) showed marked mRNA upregulation (p < 0.05). All other cytokine mRNA profiles showed down regulation (>2 fold) (p < 0.05). Conclusions: The majority of pro and anti-inflammatory cytokines mRNA levels were downregulated in severe sepsis whilst IL-10, IL-15 and IL-18 levels were upregulated. Protein profiling demonstrated elevated levels of both pro and anti-inflammatory cytokines. The inflammatory response in severe sepsis consists of both a pro and anti-inflammatory response which occur concurrently. Take-home message: Multiplex Cytokine mRNA and protein profiles have the potential to be developed inot diagnostic and prognostic biomarkers of sepsis.

O118 Inhibition of colonic basolateral potassium channels using octreotide to reduce bacterial translocation and sepsis I. Rajput, J. P. A. Lodge, G. I. Sandle University of Leeds Introduction: Translocation of bacteria and/or other substances across the

bowel wall may lead to significant sepsis. Previous evidence has demonstrated that basolateral potassium channels may be involved in regulation of tight junctions. Gut ischaemia leads to activation of intermediate conductance potassium channels (IK), and subsequent increased conductance of tight junctions. In vivo this may lead to bacterial translocation and sepis via the paracellular pathway. This study aimed to investigate the effects of potassium channel blockade on tight junctions of colonic mucosa during ischemia. Methods: Electrical current was passed across normal colonic mucosa in an Ussing chamber from which it was possible to calculate the tight junction conductance. 100 uM Dinitrophenol was administered to the mucosa to simulate ischaemia. 2 uM Somatostatin was administered to the serosal side following exposure to iscahemia. Following this, a dose response relationship was analysed using octreotide. Results: Normal tight junction conductance was 3.65 ± 1.34 mScm-1 (n = 11) versus 5.52 ± 1.22 mScm-1 in dinitrophenol treated colon (n = 10) (p = 0.003). Somatostatin administered prior to dintrophenol application (n = 6) gave a conductance of 3.28 ± 1.56, and after dinitrophenol application (n = 6) 3.48 ± 1.21 mScm-1. Both somatostatin groups demonstrated a statistically significant difference with respect to the dinitrophenoal alone group (p < 0.05). Dose response with octreotide determined that a concentration of 0.2 uM was sufficient to produce the same effect as somatostatin (n = 12). Conclusion: Octreotide has therapeutic potential in the critically ill surgical patient to reduce the incidence of bacterial translocation and post operative sepsis, thereby reducing overall post operative morbidity. Take-home message: The integrity of the gut mucosal barrier may be affected adversely by ischaemia leading to translocation of bacteria and other substances which can lead to significant sepsis. Colonic basolateral potassium channels are involved tight junction regulation, and by using octreotide to inhibit the potassium channels, it may be possible to reduce the risks of sepsis in the critically ill/surgical patient.

John Goligher Colorectal Unit, St James University Hospital Introduction: Pro and anti-inflammatory cytokines, through their interaction

with each other in complex networks, produce systemic inflammation in sepsis. Multiplex immunoassays, which allow the simultaneous measurement of multiple cytokine mRNA or protein levels from one blood sample, have the potential to be developed into biomarkers in severe sepsis. This study aimed to identify distinct gene (mRNA expression) and protein profiles of multiple pro and anti-inflammatory cytokines in severe sepsis. Methods: Patients admitted to the ICU within 24 hours of onset of severe sepsis and healthy controls were recruited by taking 1ml of whole blood. The Quantigene and Biorad Multiplex assays were used to quantify mRNA and protein levels of a range of ten pro and anti-inflammatory cytokines.


O119 Bacterial-produced polyamines interfere with the colonic mucus barrier A. C. Rogers, D. Collins, H. M. Mohan, A. W. Baird, D. C. Winter Conway Institute of Biomolecular & Biomedical Research, University College Dublin. Introduction: Polyamines (spermine, spermidine and putrescine) are

polycations present in millimolar concentrations in the gut lumen, derived

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from dietary sources and colonising bacteria. The colonic mucus barrier is formed by a layer of densely-packed negatively charged mucins and a more penetrable outer layer of mucins, in which bacteria reside. We sought to determine whether polyamines altered the permeability of the colonic mucus layer. Methods: Normal human colonic mucosa was mounted in Ussing chambers and electrophysiological parameters recorded. The apical surface was challenged with polyamines. Mucus was harvested and its properties assessed. Tissue was fixed and stained for study of mucus layer morphology. Electron microscopy (EM) was performed on fixed tissue, as well as on collected mucus. Results: Polyamines did not exert toxic effects on mucosa but caused mucus extrusion, visible ex-vivo in Ussing chambers and maximal at three minutes. Harvested mucus did not differ in dry weight between control and challenged samples indicating similar quantities of mucins were involved. EM did not show goblet cell exocytosis of treated tissues, further suggesting a direct electrostatic effect of polyamines on mucus rather than expulsion by goblet cells. Histological sections showed that mucus layer thickness was increased fivefold over control, with a loss of normal mucus layer morphology. Conclusions: Bacterial by-products in the colon alter the morphologic properties of colonic mucus, potentially allowing them to inhabit the intestinal mucus layer. This may explain how pathogenic bacteria can alter the mucus barrier allowing cellular adhesion. Take-home message: Bacterial-produced polyamines alter the morphologic properties of colonic mucus, potentially allowing them to inhabit the intestinal mucus layer. This may explain how pathogenic bacteria can alter the mucus barrier allowing cellular adhesion.

O120 Tumour necrosis factor alpha in non-inflammatory bowel disease enterocutaneous fistulas prospective study G. Rahbour, H. O. Al-Hassi, A. L. Hart, M. R. Ullah, S. M. Gabe, S. C. Knight, J. Warusavitarne, C. J. Vaizey

O121 A novel ’non-SLIP’ MICRO-structured surface for atraumatic surgical manipulation G. W. Taylor, A. Neville, P. R. Culmer, R. Roshan, J. Barrie, D. G. Jayne University of Leeds Introduction: Instrument trauma during laparoscopic surgery leads to a local

tissue inflammatory response that contributes to post-operative ileus, adhesions, and loss of gut barrier function. It may also lead directly to iatrogenic injury. We tested alternative surfaces for atraumatic tissue handling. Methods: Three surfaces were tested: i) a newly fabricated micro-pillar array (3µm diameter, 3µm height); ii) pyramids (3µm height); iii) nano-scale rounded asperities (250nm); and compared to a non-structured flat surface (control). Adhesion was measured by contact/retraction cycles on fresh rat peritoneum by optically recording deflection via a spring cantilever. Data were recorded as force-displacement plots. Friction to the peritoneum was observed as the minimum lateral shear force that could be applied to the interface before slippage occurred. Results: The micro-pillar surface displayed a significant increase in adhesive force versus the flat surface (mean 67mN versus 30mN; p = 0.0004). No significant improvement was seen for the nano-structure (33mN) or pyramids (15 mN). Analysis of the force-displacement plots showed the peritoneum being pulled into contact. The micro-pillars generated a mean friction coefficient of 1.54 (mean lateral friction 430mN from a loading force of 280mN). The other surfaces were unable to generate any measurable friction. Conclusions: A micro-pillared surface is the preferred surface for atraumatic adhesion to the peritoneum. The attachment to the lubricated peritoneum is probably due to the formation of capillary bridges and the resulting attractive meniscal forces. Its application to laparoscopic instruments may provide the ideal ’non-slip’ surface for atraumatic tissue manipulation. Take-home message: A novel micro-pillared array provides an atraumatic ’non-slip’ interface with the peritoneum. When applied to laparoscopic tools, the surface may reduce the trauma and complications of surgical manipulation.

O122

St. Mark’s Hospital and Academic Institute Introduction: The aim of this study is to assess the inflammatory activity, with a particular emphasis on tumour necrosis factor alpha (TNF-α) of non-

inflammatory bowel disease enterocutaneous fistula (non-IBD ECF) when compared with control small bowel terminal ileum tissue. If this study can show the presence of TNF-α in the fistula tract then there would be a potential for a novel therapy for patients with persistent ECF not associated with IBD. Methods: Research ethics approval was granted for this study. Tissue biopsies were obtained from ECF at operation from non-IBD patients and from the terminal ileum in normal colonoscopy control patients. After 24 hours incubation, intra cellular staining was performed using monensin to assess the on-going intra cellular production of cytokines. Data was acquired using FACS Canto II. Results: The student t-test for non-paired data was used. Production of TNFα by dendritic cells from non-IBD ECF tissue was significantly higher than that from control terminal ileum tissue (p = 0.0008). All viable cells from non-IBD ECF tissue also produced significantly higher level of TNF- α compared with control tissue (p = 0.01). Conclusions: A trend has been found in the on-going production of cytokines in non-IBD ECF compared with control tissue. Addition of a greater number of samples may show significant differences between the two groups of patients and provide validity to this trend. This data is encouraging and may provide evidence for the potential use of anti-TNF- α agent in the treatment of non-IBD ECF. Take-home message: Thus far this study reveals encouraging results and may provide evidence for the potential use of anti-TNF- α agent in the treatment of non-IBD ECF.


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Vitamin C ameliorates renal injury in a murine model of contrastinduced nephropathy K. E. Rollins1 , A. Noorani1 , L. Janeckova2 , M. Griffiths1 , M. P. Baker2 , J. R. Boyle1 1 Vascular Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, 2 Antitope Ltd, Babraham Science Park, Cambridge

Introduction: Contrast induced nephropathy (CIN) is the commonest cause

of iatrogenic renal injury; its incidence has increased with the advent of complex endovascular procedures. Evidence suggests that ascorbic acid has a nephroprotective effect in percutaneous coronary interventions. The aim of this study was to evaluate the therapeutic effect of ascorbic acid in an in vivo murine model of CIN. Methods: A total of 24 mice were divided into 4 groups. Three groups were exposed to high doses of contrast media (omnipaque) in a well-established model of CIN. These groups were subsequently treated with low or high dose ascorbic acid (AA) or placebo (saline). Urine was analysed for NGAL, a sensitive marker of renal injury. All mice were sacrificed at 3-days and kidneys were analysed by immunohistochemistry for caspase-3, NGAL and TUNEL to assess apotosis. Kidney lysates were analysed by ELISA. Results: Urinary NGAL:creatinine ratio was significantly lower after AA treatment with 44% and 62% reduction in the low and high dose groups respectively at 48 hours. TUNEL and caspase-3 expression in both ascorbic acid groups was reduced compared with the positive control, particularly the high dose group. There was a 50% reduction in NGAL ELISA expression following low dose ascorbic acid, although this degree of protection was not observed in the high dose group. Conclusions: Ascorbic acid ameliorated the contrasted induced renal injury in this murine model of CIN. Further work is required to establish whether

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vitamin C can reduce the incidence of CIN in humans undergoing complex endovascular procedures. Take-home message: Our murine model demonstrates the potential use of ascorbic acid as a nephroprotective agent against contrast-induced nephropathy.

O123 Identification of LINE1 chimeric transcripts in cancer using bioinformatics approaches

β-catenin protein, expression of the β-catenin/Tcf target gene AXIN2 and expression of the target gene WNT11 were detected only in the desmoid cell line. However, and total β-catenin protein levels did not differ among the cell lines. Conclusion: The Wnt/β-catenin signalling pathway is active in desmoid cells. WNT11, a β-catenin/Tcf target that can activate noncanonical Wnt signals is overexpressed. Take-home message: This is the first study demonstrating activation of both canonical and non canonical Wnt signalling pathways in FAP desmoid tumour.

H. Xu1 , A. Aboobaker2 , J. N. Lund1 , C. Tufarelli1

ORAL PRESENTATIONS 3C POSTERS OF DISTINCTION

1 School of Graduate Entry Medicine and Health, Royal Derby Hospital, University of Nottingham, 2 Department of Zoology, University of Oxford

Introduction: The majority of our genome (55%) is composed of transposable

elements (TEs), often described as ‘‘junk DNA’’ while protein-coding regions only account for 1.5% of it. LINE1 elements are the most successful TEs and comprise about 20% of our genome. LINE1 elements are usually silenced in normal somatic cells. However, in cancer they are often less methylated and expressed. This can result in expression of LINE1 chimeric transcripts that may contribute to the development of carcinoma. Although next generation sequencing technologies allow unbiased sequencing of the transcriptome, available bioinformatics tools discard all sequences containing repetitive elements so that these transcripts have remained under-investigated. The purpose of this study was to develop software for the identification of LINE1 chimeric transcripts (LCTs) in transcriptome datasets. Methods: A software (TECDetec) was developed to identify LCTs in transcriptome datasets generated using paired-end RNA sequencing from matched normal and tumour colon samples. Biological significance of the LCTs detected was analyzed using bioinformatics approaches. Results: The software identified LCTs in transcriptomic datasets. Tumour tissues were found to express twice the amount of LCTs than their matched normal tissue. LCTs that were downregulated or upregulted in a tumour specific manner in both patients were found. Comparison with gene ontology (GO) terms revealed LCTs with potential role in cancer. Conclusions: TECDetec successfully identifies LINE1 chimeric transcripts providing novel potential biomarkers whose functional role in carcinogenesis is worth further investigation. Take-home message: Bioinformatics pipeline TECDetec was developed for detecting LINE1 chimeric transcripts whose functional role in carcinogenesis is worth further investigation.

O124 In vitro studies of the Wnt signalling pathways in FAP desmoid tumour S. Bhandari1 , P. Uysal Onganer2 , D. Romero2 , R. K. Phillips1 , R. Kypta2 , S. K. Clark1 1 St Mark’s Hospital, 2 Institute of Reproductive and Developmental Biology, Imperial

P01 Computational modelling of embolic travel trajectory in cerebral arteries: Influence of micro embolic particle size and density F. Dario1,3 , Q. Long1 , S. Das1,2 , M. Pinelli3 1 Brunel Institute for Bioengineering, Brunel University, Uxbridge, 2 Department

of Vascular Surgery, Hillingdon Hospital NHS Trust, Hillingdon, Middlesex, UK, 3 Facoltà di Ingegneria, Università di Ferrara, Ferrara, Italy

Introduction: Ischemic stroke is responsible for 80% of stroke cases.

Prevention of the reoccurrence of ischemic attack is the major treatment target. Accurate diagnosis of the emboli source for a specific infarction lesion is very important for a better treatment for the patient. However little is known of embolic particle flow trajectory and its behaviour in complex cerebral arterial network. This study aims to study the embolic particle trajectories in a cerebral arterial network, and the influence of particle size, mass and release location to the particle distributions, by computational modelling. Methods: The cerebral arterial network model was generated from MRI images. Particles with diameters of 200, 500 and 800 micron and densities of 800, 1030 and 1300 kg/m3 were released in the carotid and basilar arteries. A fully coupled scheme of particle and blood flow interaction in a software ANASYS_CFX13 was used in the simulations. Results & Conclusions: The results show that heavy particles (density large than blood) travel slowly than local blood; larger or lighter particles are more likely to travel to large branches in cerebral arteries. In certain cases, all large particles go to the middle cerebral arteries; large particles with higher travel speeds in large arteries are likely to travel at more tortuous trajectories; particles started from the central part of the feeding vessel are unlikely to go to the anterior cerebral arteries while those starting from the near wall conversely are unlikely to move to the posterior cerebral arteries. Take-home message: There is a regular pattern of embolic particle distribution in cerebral arterial network. Embolic particle travel trajectory is influenced by particle size, density and its release location.

College London Introduction: The Wnt signalling pathway is important for cell proliferation

and differentiation and is implicated in tumorigenesis. Activation of canonical Wnt signalling leads to β-catenin stabilisation and expression of β-catenin/Tcf target genes, including WNT11, a non-canonical Wnt that activates β-cateninindependent signals. In FAP desmoids, the canonical Wnt signalling pathway is thought to be constitutively active as a result of mutations in the APC gene. Using a primary desmoid tumour cell line from an FAP patient, we studied activation of Wnt signalling pathways in vitro. Method: One desmoid, one FAP fibroblast and one non-FAP fibroblast cell line were used. Full sequence APC mutation analysis was performed to confirm the desmoid cell line. Immunocytochemistry, Immunohistochemistry, western blotting and PCR were used to determine expression of β-catenin and Wnt target genes. Results: Mutations on both APC alleles were detected in the desmoid cell line (germline mutation: codon 1132; somatic mutation: codon 1438). Nuclear


P43 Posters of Distinction Prize Winner Adult stem cells in the human and mouse spinal cord: What are their characteristics and can they migrate and replicate upon exposure to growth factors S. Stokes1,2 , N. Mani (1.2), A. Bahl2 , L. O’Connor-Read1,2 , M. Placzek1 1 MRC Centre for Developmental and Biomedical Genetics, University of Sheffield, Sheffield, UK, 2 Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK

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Introduction: There are distinct regions in the adult mouse and human central

nervous system which harbour neural stem/progenitor cells (NSPCs). Although a stem cell niche has been proposed in the mouse brain, the characterisation of a niche within both the mouse and human spinal cord is limited. Methods: Human spinal cord tissue was surgically retrieved from human organ donors across Yorkshire and cultured in enhanced media, which has previously isolated and expanded NSPCs. To examine the endogenous properties of the stem cell niche, immunohistochemistry and in-situ hybridisation assays were employed to study the protein and mRNA expression profiles in the adult mouse and human spinal cord. To analyse the intact stem cell niche ex vivo, a slice culture assay was developed where NSPCs could replicate within complete transverse spinal cord sections. Results: We were not only able to demonstrate the dramatic proliferative effects of exogenous growth factors upon the intact spinal cord NSPC niche; we also observed migration of these NSPCs within intact tissue which has undergone significant damage. Moreover, expression profiles of important NPSC markers varied between the mouse and human. Furthermore, highly restricted mRNA expression patterns were observed of genes implicated in the maintenance of neural crest progenitors, embryonic stem cells and NSPCs elsewhere in the CNS. Conclusions: In summary, we demonstrate both similarities and differences between the NSPC niche across the two species and those located elsewhere in the CNS. We demonstrate exogenous growth factors cause proliferation of NPSCs in the human spinal cord which may aid recovery, following injury. Take-home message: We show key differences, in the mouse and human spinal cord stem cell niche, suggesting that the mouse stem cell niche may not be a adequate model of the human stem cell niche. In addition, we determine that adult human spinal cord stem cells may have a capacity to enhance the recovery of spinal cord injured patients.

P10 Primary and secondary care attitudes to the management of superficial venous thrombosis

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P55 The impact of screening on clinicopathological determinants of outcome in colorectal cancer in the West of Scotland Y. Grant1 , D. Mansouri1,2 , E. Crighton2 , D. McMillan2 1 University of Glasgow, 2 Glasgow Royal Infirmary

Introduction: Screening for colorectal cancer increases detection of early

stage disease. However, independent of stage, other tumour and host prognostic factors have been shown to affect outcome. The aim of this study was to examine the prevalence of these clinicopathological features in screen-detected colorectal cancers. Methods: Patients with a positive FOBT in NHS Greater Glasgow & Clyde were offered colonoscopy where appropriate. The outcomes of colonoscopy were collected retrospectively from the Scottish Bowel Screening Database. Variables were analysed using χ2 tests for linear trend on SPSS software. Results: Between November 2010 and April 2011, 1266 patients attended for colonoscopy through screening in NHS Greater Glasgow & Clyde. Cancer was detected in 105 patients (8%). Increased risk of cancer at colonoscopy was associated with male sex (p < 0.001) and increasing age (p < 0.001). Dukes stage was A 42 (40%) patients, B 24 (23%) patients, C 31 (30%) patients and D 8 (8%) patients. Advancing T-stage was associated with nodal involvement (p < 0.001), peritoneal involvement (p < 0.001) and vascular invasion (p < 0.05). Only vascular invasion was present in a significant proportion of T1 (26%) & T2 (44%) tumours. The systemic inflammatory response, as measured by the modified Glasgow Prognostic Score (n = 48) and Neutrophil-to-Lymphocyte Ratio (n = 80), was elevated in 14% and 11% of cancer patients, respectively. Conclusion: The adoption of screening has created a substantial stage migration towards earlier presentation in colorectal cancer. Vascular invasion appears to be an early feature in the natural history of the disease and may have important clinical implications in the screened population. Take-home message: Screening increases the proportion of Dukes A and B cancers diagnosed, which is likely to improve cancer-specific survival. Vascular invasion appears to be a prominent feature of these early stage tumours and may be used to select appropriate screen-detected patients for adjuvant chemotherapy in the future.

T. R. A. Lane, K. Sritharan, I. J. Franklin, A. H. Davies Academic Section of Vascular Surgery, Imperial College, Charing Cross Hospital, London, UK

P23

Introduction: To establish attitudes towards management of superficial venous

Assessing the factors contributing to the presentation of women within the screening age to symptomatic breast clinics

thrombosis (SVT) in primary and secondary care. Methods: A 19 question survey evaluating referral and management patterns for SVT was designed and validated. General Practitioners (GPs) and Consultant members of the Vascular Society (VSs) in the UK were invited by e-mail to complete the online survey. Results: 369 surveys have been completed. 70% saw 0.05) Sphincter integrity on endoanal ultrasound was comparable between the 2 groups (p > 0.05) Patients that failed to respond to temporary SNS demonstrated partial rectal hyposensitivity, as recorded by the sensory threshold of ‘‘urge to defecate’’ that differed significantly from the patient group that responded to temporary SNS (p = 0.04) The remaining anorectal electrophysiology variables did not differ significantly between the 2 groups (p > 0.05). Conclusion: The lack of correlation, with the exception of one variable, between electrophysiology and temporary SNS outcome questions the need to perform these tests prior to SNS. It also raises questions about our understanding of the complex mechanisms of continence. SNS: Sacral Nerve Stimulation. Take-home message: There is limited evidence available of what factors predict outcome of temporary SNS. We identified 2 factors that influence patient selection and may trigger further research on the pathophysiology of continence.

P04 A preliminary study of photoplethysmography and laser doppler to identify reduced perfusion: A role in acute compartment syndrome? H. T. Shalabi, E. Lincoln, C. Mann, J. Teoh, S. T. Shalabi, J. Crowe, B. Hayes-Gill, D. Sharkey School of Clinical Sciences, University of Nottingham Introduction: Delayed diagnosis of acute compartment syndrome (ACS) can

result in significant morbidity. Early clinical diagnosis is difficult especially in children or patients who are unconscious. Invasive pressure measurements are difficult to interpret and can be painful, highlighting the need for better techniques of detecting early ACS. We have developed a novel photoplethysmography (reflectance-PPG) device which identifies changes in cutaneous perfusion, and hypothesised it could indentify early ACS. The aim of this proof of principle study was to investigate the potential to detect decreased cutaneous perfusion in a model of ACS. Methods: Our device was compared with commercially available transmissionPPG and Laser Doppler (LD) devices, using an established tourniquet compression model of ACS, on the anterior compartment of the forearm of 23 healthy adult volunteers. Pressure intervals were chosen to simulate threatened ( < 30mm Hg), established (30-60mm Hg) and extreme (>systolic BP) ACS. Ethical approval was given. Results: All three devices detected statistically significant changes in cutaneous perfusion. However, only our reflectance-PPG device was able to detect a significant perfusion difference (P < 0.001) in the lower pressure ranges (≤20mm Hg) coincident with early ACS. Conclusion: Our reflectance-PPG device could be used for the early detection of impending ACS. Such an inexpensive, non-invasive and reliable device could be useful in those at risk of ACS especially children or unconscious patients. It may also have a role in the early detection of cardiovascular shock (e.g. septicaemia) before changes in blood pressure are apparent. This work requires further validation in these groups of patients. Take-home message: Our reflection-PPG device could be used for the early detection of impending acute compartment syndrome. It may also play a role in the early detection of cardiovascular shock (e.g. septicaemia).


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P26 Raising the standards of outcome reporting in reconstructive breast surgery – initial results of the BRAVO (breast reconstruction and valid outcomes) study, a multicentre consensus process to develop a core outcome set J. Ward1 , S. Potter1 , S. Cawthorn2 , C. Holcombe3 , R. Warr4 , S. Wilson4 , R. Tillett4 , E. Weiler-Mithoff5 , Z. Winters6 , J. Barker2 , C. Oates4 , D. Harcourt7 , S. Brookes1 , J. Blazeby1,6 1 Centre for Surgical Research, School of Social and Community Medicine, University of Bristol, 2 Breast Cancer Centre, North Bristol NHS Trust, 3 Liverpool and Broadgreen NHS Foundation Trust, 4 Department of Plastic Surgery, North Bristol NHS Trust, 5 Canniesburn Plastic Surgical Unit, 6 University Hospitals Bristol NHS Foundation

Trust, 7 Institute for Appearance Research, University of the West of England Introduction: Careful selection of outcomes is important if research

is to inform clinical practice and direct policy. Systematic reviews(SRs) in reconstructive breast surgery(RBS) however have demonstrated marked heterogeneity in the selection, definition and reporting of key outcomes limiting cross-study comparison and research synthesis. The development of a core outcome set(COS)–a scientifically agreed-upon minimum set of outcomes that should be measured and reported in RBS studies, may resolve this issue. We report the initial results of the BRAVO (Breast Reconstruction and Valid Outcomes) Study which aimed to develop a COS for RBS. Methods: A survey was developed from a long-list of outcomes identified from SRs and qualitative work with key stakeholders and sent to a purposive sample of patients and professionals involved in the provision of specialist care. Participants were asked to prioritise outcomes on a scale of 1(unimportant) to 9(extremely important). The proportion of respondents rating each outcome ‘very important’ (score of 7–9) was compared and contrasted between participant groups. The study received full ethical approval (REC ref:11/SW/0305). Results: The response rate was 49.5% (126/274-patients;87/156professionals). There was agreement between seven out of 10 most highly-ranked outcomes including patient-reported cosmesis, cosmetic satisfaction and early complications. Patients, but not professionals rated generic complications including bleeding as important, whilst professionals rated psychosocial issues including self-esteem, more highly than patients. Conclusion: Patients and professionals prioritise similar outcomes, but some discrepancy exists. Further work in which participants will be asked to reprioritise the list will be necessary to identify just seven key outcomes which form the final-COS. Take-home message: Patients and healthcare professionals broadly agree which outcomes of reconstructive breast surgery should be measured in research and audit studies. Further work is needed to identify which outcomes are the most important and should be included in a core outcome set.

P08 Single visit endovenous laser treatment for symptomatic saphenofemoral incompetence has better patient outcome on mid-term followup L. S. Alder2 , M. A. Rahi1 1 Royal Blackburn Hospital, 2 Imperial College London

Introduction: Endovenous ablation of saphenous varicose veins has decreased

morbidity and recovery time when compared to open surgery. We assessed the outcome and mid-term patient satisfaction of single-visit endovenous laser treatment (EVLT) alone, combined with phlebectomies or endovenous chemical ablation. Methods: We conducted a retrospective review of all consecutive patients (n = 91) in 2008–2009 who underwent single visit day-case EVLT using local anaesthesia under one surgeon. Postoperative venous ultrasound at 2 and 14 months were reviewed. A telephone questionnaire to assess recurrence of symptoms and quality of life (QoL) was performed at 42 months. Results: 124 limbs underwent day case EVLT under local anaesthesia using 810nm Diode Laser at continuous 14W setting. EVLT alone included 48 limbs,

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EVLT with phlebectomies n = 50 limbs, EVLT with endovenous chemical ablation n = 26 limbs. 91% of limbs underwent a 2 month post-operative scan. 100% had satisfactory GSV ablation (n = 1 anterior thigh vein patency), 82% successfully underwent a 14month scan with a 98% GSV ablation, 2.9% had anterior thigh vein and SFJ incompetence. Recurrence of GSV patency and reflux was 130 cm2 ) or low visceral obesity (LVO, area 40%). Results: Co-expression of MDMX with MDM2 was observed in 32 cases. Free P53 expression was diminished at higher MDM2 : MDMX ratios but some minimal level of MDMX was required to achieve significant P53 down regulation. Conclusions: Variable degrees of P53 deactivation are commonly seen in liposarcomas due to interactions with MDM2 and MDMX. This observation may suggest better response to dual blocker compounds in cases that significantly express MDMX in conjunction with MDM2, but further studies are required to ensure the proportionate inhibition is optimum. Take-home message: Careful analysis of MDM / P53 expression profiles may guide the selection of targeted novel therapies in human liposarcomas.

Introduction: A 3D in vitro colorectal cancer model which mimics the

microarchitecture of solid cancers, incorporating gold nanoparticle (GNP) inclusions at typical concentrations found in vivo, was developed in order to provide a more controllable replacement to small-animal models for assessment of imaging techniques. Methods: Colorectal cancer cells (HT29) and fibroblasts (3T3) were incubated with varying GNP concentrations (0.5-5 mg/ml). Using tissue engineering (plastic compression) technologies we combined HT29 cells and collagen type I to create a dense, artificial cancer mass (ACM). To reflect the in vivo microenvironment, the ACM was nested into fibroblast populated


0130 M-THPC delivery via pegylated plga nanoparticles for in vivo photodynamic therapy (PDT) M. J. Bovis, J. H. Woodhams, M. Rojnik, P. Kocbek, J. Kos, S. G. Bown, A. J. MacRobert, M. Loizidou University College London

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Introduction: Photodynamic therapy (PDT) is a treatment for malignant and

Take-home message: A resorbable nanocomposite trachea and bronchi

certain non-malignant diseases that uses a light-activated photosensitising agent to induce necrosis mediated by the production of reactive oxygen species. Metatetrahydroxyphenyl chlorin (m-THPC) is a potent photosensitiser currently available; however, ways to improve m-THPC selective uptake in tumour tissue are being investigated to reduce adverse side-effects. PEGylated polymeric nanoparticles (PEG-PLGA NPs) have been developed to achieve more efficient uptake of m-THPC through increased circulation time and bioavailability to improve PDT efficacy. Methods: m-THPC in its standard formulation (Foscan) and PLGA mTHPC nanoparticles (PLGA & PEG-PLGA) were injected i.v. into normal and tumour bearing rats (0.3 mg kg-1) to compare the pharmacokinetics of m-THPC between formulations. PDT was performed at drug light intervals (DLIs) of 24 and 72 h to assess tumour necrosis. All animal experiments were carried out under the authority of project and personal licences granted by the UK Home Office and with reference to NCRI (National Cancer Research Institute) guidelines for the Welfare of Animals in Experimental Neoplasia (2010). Results: Pharmacokinetic data revealed m-THPC in PEG-PLGA NPs appeared to accumulate less in normal tissues than when encapsulated in PLGA NPs and greater in tumour at 72 h compared to standard m-THPC. However despite this, there appeared to be limited differences in tumour PDT efficacy between all formulations and DLIs. Conclusion: These long-circulating novel PEGylated PLGA NPs appear to improve accumulation of m-THPC in tumour tissue but in vivo tumour models may be a limiting factor in measuring PDT effect. Take-home message: There is potential to improve the efficacy of photodynamic therapy through nanoparticle drug delivery.

scaffold has been developed as a potential tissue-engineered solution to the increasing number of tracheal anomalies and pathologies in clinics.

O131 The development of resorbable nanocomposite trachea and bronchi scaffolds for paediatric applications: A tissue engineering solution to organ transplantation G. Z. Teoh1 , C. Crowley1,2 , M. Birchall1,2 , A. M. Seifalian1 1 University College London, 2 UCL Centre for Nanotechnology and Regenerative

Medicine, Division of Surgery and Interventional Sciences, UCL Ear Institute, Royal National Throat, Nose & Ear Hospital), London, U.K. Introduction: Congenital tracheal defects and prolonged intubation following

premature birth have resulted in an unmet clinical need. Advances in stem cell technology, tissue engineering and material sciences have inspired the development of our resorbable, nanocomposite trachea and bronchi scaffold. Methods: A bifurcated scaffold was designed and constructed using our novel, resorbable nanocomposite polymer, Polyhedral Oligomeric Silsesquioxane Poly(ε-caprolactone) Urea Urethane (POSS-PCL), integrated with Polyhedral Oligomeric Silsesquioxane Poly(carbonate-urea) urethane for additional mechanical strength. Material characterisation studies included polymer viscosity, tensile strength, suture retention and contact angle. Bone marrow derived mesenchymal stem cells (bmMSCs) and human tracheobronchial epithelial cells (HBECs) were cultured on POSS-PCL for 14 and 8 days respectively and the metabolic activity was assessed by Alamar Blue assay. Quantum dots conjugated to RGD peptides and anti-collagen type I antibody were utilised to examine cell migration throughout the scaffold. Results: POSS-PCL exhibited good mechanical properties and the relationship between the casted and coagulated polymer layers was comparable to the relationship between the cartilaginous U-shaped rings and interconnective cartilage of the native human trachea. Good suture retention was also achieved. Cell attachment and a significant, steady increase in proliferation was observed, as illustrated by two-way ANOVA (bmMSC: p = 0.001; HBEC: p = 0.003). Quantum dot studies illustrated cell penetration throughout the scaffold. SEM images confirmed the attachment and proliferation of both cell lines as well. Conclusion: Our mechanically viable scaffold successfully supports bmMSC and HBEC attachment and proliferation demonstrating its potential as a tissue-engineered solution to the increasing number of tracheal anomalies and pathologies in clinics.


O132 Impact of non-digestible carbohydrate on methylation of GADD45A promoter in the human colon C. Jones, N. Willis, I. McCallum, J. C. Mathers Institute of Ageing and Health Introduction: Methylation is an epigenetic modification that changes gene

expression without altering the genetic code. Patterns are plastic and change with environment e.g. diet. In cancer, hypermethylation of CpGs (cytosine guanine dinucleotides) in the promoter region of tumour suppressor genes leads to silencing and can initiate tumourgenesis. GADD45A is a candidate tumour suppressor gene. Decreased expression in colorectal cancer (CRC) and re-expression with intervention of non-digestible carbohydrate (NDC) has previously been shown. The mechanism for this is unknown. Aim: To quantify methylation of GADD45A in normal colonic mucosa and identify changes in response to dietary intervention. Measure methylation of GADD45A in mucosa from patients with polyps and ulcerative colitis (UC) and compare to normal mucosa. Methods: DNA from human colorectal mucosal samples collected in the DISC study was used. DISC was a placebo controlled, 50 day intervention study with NDC. Samples were collected before and after intervention. DNA was bisulphite modified and methylation across 4 CpG sites was measured using pyrosequencing. Results: The mean methylation across all 4 CpG sites was 2.24%. Dietary intervention had no effect on methylation. Methylation in polyp and UC samples was significantly increased at CpGs 1 and 2 (p < 0.05). Conclusions: Low methylation was seen in normal mucosa and remained unchanged with intervention. It was expected that methylation would decrease with intervention however levels were low to begin with. The polyp and UC samples, which have a higher risk of developing CRC, had higher methylation. Future work would include quantifying methylation of GADD45A in tumour tissue. Take-home message: Hypermethylation is a mechanism that can initiate tumourgenesis. Methylation of GADD45A did not decrease with dietary intervention with non-digestible carbohydrate in normal samples, however methylation was higher in UC and polyp samples.

ORAL PRESENTATIONS 5A VASCULAR 2

O133 Norman Williams Prize Winner Microemboli identified in the right heart during thermoablation of varicose veins V. Sounderajah, H. M. Moore, A. Thapar, T. R. A Lane , K. F. Fox, I. J. Franklin, A. H. Davies Academic Section of Vascular Surgery, Department of Surgery and Cancer, Imperial College School of Medicine Introduction: Cerebrovascular events reported following foam sclerotherapy

for varicose veins are hypothesised to be caused by migration of microemboli to the brain through a cardiac septal defect. Neurological events are not reported during endothermal ablation of varicose veins. The aim of this study was to identify whether microemboli are present in the right heart during endothermal ablation.

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Methods: Ethical approval was obtained, reference number 11/LO/1358.

Transthoracic echocardiography was performed during local anaesthetic radiofrequency ablation of the great saphenous vein in 14 patients. Apical views were captured before the procedure, during heating cycles and at one minute after treatment. Patients were monitored for one hour. Video loops were read by an independent cardiologist and the sonographer. The presence of microemboli was classified as: 0 = absent, 1 = occasional, 2 = stream, 3 = complete opacification. Results: Loops were of diagnostic quality in 11/14 (79%) patients. After the second cycle of heating, microemboli moving through the right heart were seen in 5/11 (45%) patients. These were classified as grade 1 in 4 patients and grade 2 in 1 patient. No microemboli were seen in the left heart. Inter-reader κ was 0.5 (95% CI 0.2-0.79). No neurological symptoms were reported. Conclusion: Microemboli in the right heart are a common finding during radiofrequency ablation of varicose veins. Considering the prevalence of cardiac septal defects (26%), more neurological events would be expected if these particles were responsible for these events. Further work is required to elicit the mechanisms underlying neurological complications following sclerotherapy. Take-home message: Microemboli are found in the right heart during radiofrequency ablation of varicose veins. Further work is required to elicit the mechanisms underlying neurological complications following sclerotherapy.

O134 Comparison of the effect of open and endovascular (EVAR) aneurysm repair on renal function A. Saratzis1 , P. Sarafidis2,3 , D. Christopoulos2 , D. Kiskinis2 , G. D. Kitas1 1 Department of Research and Development, Dudley Group NHS Foundation Trust, Russells Hall Hospital, Dudley, West Midlands, UK, 2 Department of Vascular Surgery, Aristotle University of Thessaloniki, Greece, 3 Department of Renal Medicine, King’s

College, London, UK Introduction: Repair of an abdominal aortic aneurysm (AAA) can lead to

several renal complications. The medium-term effect of the various types of AAA repair on renal function has not been adequately investigated using glomerular filtration rate (GFR). Methods: Patients were recruited from an international prospective AAA database and were matched for age, gender, AAA diameter, hypertension and smoking-status; GFR was calculated using the CKD-EPI formula at 0, 6, 12 and 18 months. Three groups (nested case-controlled analysis) were constructed (group 1: open-repair; group 2: EVAR, suprarenal-fixation; group 3: EVAR, infrarenal-fixation). Results: A total of 75 patients were included and followed-up for ≥18 months (6 females, mean age: 71 ± 7 years, mean AAA diameter: 6.6 ± 1.3 cm). eGFR at baseline did not differ significantly between groups (p = 0.3) and during follow-up was group 1: baseline 76 ± 27, 6 months 66 ± 20, 12 months 66 ± 18, 18 months 70 ± 21; group 2: 81 ± 45, 74 ± 38, 70 ± 37, 70 ± 37; group 3: 92 ± 43, 91 ± 41, 90 ± 38, 90 ± 44 ml/min/1.73m2). Open repair had a significant impact on eGFR at 6 (mean drop 0–6 months: 10 ml/min/1.73m2, p = 0.003) and 12 months (mean drop 0–12 months: 10 ml/min/1.73m2, p = 0.003). A slight increase (4 ml/min/1.73m2) occurred at 18 months (p = 0.02). Suprarenal-fixation EVAR had a significant impact at 12 months (mean drop 0–12 months: 11 ml/min/1.73m2, p = 0.003), not continued after the 1st year (p = 0.74). eGFR did not drop significantly after infrarenal-fixation EVAR. Conclusion: Open AAA repair and EVAR using suprarenal-fixation have a significant impact on renal function during the first post-operative months which is not sustained after the first year. Take-home message: This is the first prospective controlled analysis that uses the most contemporary estimate of renal function (eGFR using the CKDEPI formula) to compare the effect of open AAA repair and endovascular repair using both suprarenal and infrarenal fixation devices. The drop in eGFR seen after 12 months was not sustained at 18 months.


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O135 Is there a role for C-reactive protein, myeloperoxidase or Beta-2-microglobulin as a marker of carotid plaque instability? R. K. Birk1 , M. K. Salem1 , K. West2 , D. Moore2 , A. Nicolaides3 , R. D. Sayers1 , A. R. Naylor1 , M. J. Bown1 1 Vascular Surgery Group, Department of Cardiovascular Sciences, Robert Kilpatrick Clinical Sciences Building, University of Leicester, 2 Department of Histopathology, University Hospitals Leicester, 3 Department of Vascular Surgery, Imperial College,

London Introduction: The aim of this study is to evaluate the roles of C-Reactive

Protein (CRP), Myeloperoxidase (MPO) and Beta-2-Microglobulin (B2M) as potential biomarkers of carotid plaque instability. Methods: Plasma samples from symptomatic (n = 122) and asymptomatic (n = 27) patients undergoing carotid endarterectomy (CEA) were analysed for CRP, MPO and B2M levels using enzyme-linked immunosorbent assays (ELISAs). Plasma protein levels were then correlated with defined clinical, Duplex ultrasound and validated histological criteria of plaque stability using non-parametric statistical tests. Results: Plasma CRP levels were significantly elevated in symptomatic patients (median = 2.80 mg/L) compared with asymptomatic patients (median = 1.53 mg/L, P = 0.02). Plasma CRP levels were not, however, associated with any histological or imaging features of plaque instability and did not correlate with recency of symptoms in symptomatic patients. Plasma MPO levels were not related to any clinical, imaging or histological criteria of plaque instability. Plasma B2M was significantly elevated in asymptomatic patients (median = 8.21 mg/L) compared with symptomatic patients (median = 5.60 mg/L, P = 0.002), and there was no association between B2M and the recency of symptoms. Plasma B2M levels correlated significantly with histological evidence of intraplaque haemorrhage (P = 0.013). Conclusions: Plasma biomarkers offer the potential to guide interventions such as CEA, but two of the three biomarkers tested in this project failed to demonstrate significant correlation with histological, clinical or imaging criteria of unstable plaques. However, the novel finding that elevated plasma B2M was increased in the presence of intraplaque haemorrhage suggests the use of B2M in identifying ’high risk for stroke’ asymptomatic patients in the future. This finding requires validation in an independent cohort. Take-home message: The measurement of plasma biomarker levels may be of use in the selection of patients for carotid endarterectomy, through the identification of unstable internal carotid artery plaques. However, large scale studies are required to evaluate the clinical role of potential biomarkers.

O136 High-density lipoprotein cholesterol and abdominal aortic aneurysm – a mendelian randomisation study S. C Harrison1 , M. V. Holmes1 , F. W. Asselbergs on behalf of the SMART study2 , M. J. Bown on behalf of the Aneurysm Consortium3 , A. F. Baas on behalf of the Utrecht Study2 , S. Grettarsdottir on behalf of the Iceland Study4 , G. T. Jones on behalf of the New Zealand Study5 , S. E. Humphries1 1 University College London, 2 Utrecht Medical Centre, 3 Leicester University, 4 Decode

Genetics, Iceland, 5 Otago University Lower circulating high-density lipoprotein cholesterol (HDL-C) has been associated with increased risk of AAA, but it is not clear if this is a causal relationship. Genotypes are randomly assigned at conception and can be used as instruments to investigate causality. First, systematic review and meta-analysis of the published literature was performed to define the association between HDLC and AAA. Two novel mendelian randomization analyses were then carried out. First, a genetic risk score composed of 35 single nucleotide polymorphisms (SNPs) associated with higher HDL-C levels was tested for association with AAA. Second, a SNP in the promoter of CETP, with a range of effects similar to CETP-inhibition was tested for an association with AAA. Six studies (1,056 cases, 21,450 controls) reported an odds ratio for AAA per unit change in

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HDL-C concentration, adjusted for other traits. A one SD increase in HDL-C was associated with lower risk of AAA (OR 0.69, 95% CI 0.63 – 0.76, I2 = 0%, P = 4.1 × 10−16 . In analysis of 2,367 cases and 44,437 controls from two studies, one SD increase in weighted genetic risk was associated with a lower risk of AAA (OR = 0.89, 95%CI 0.86-0.93, P = 2.4 × 10−7 ). rs3764261 in CETP was also associated with a lower risk of AAA in meta-analysis of data from 5 cohorts (4,889 cases and 52,482 controls). Instrumental variable regression showed consistent results from observational and genetic data. This study suggests that HDL-C mediated pathways play a causal role in AAA pathogenesis. Trials of CETP inhibition in AAA may be warranted. Take-home message: These results suggest that genetically lowered HDLC is causally related to development of AAA, and therefore HDL-C is a valid therapeutic target.

O137 The association between endothelial nitric oxide synthase (eNOS) and methylene tetrahydrofolate reductase (MTHFR) polymorphisms and abdominal aortic aneurysm (AAA) A. Saratzis1 , M. J. Bown2 , J. B. Wild2 , R. D. Sayers2 , J. P. Smith1 , G. D. Kitas1 1 Department of Research and Development, Dudley Group NHS Foundation Trust, Russells Hall Hospital, Dudley, West Midlands, 2 Department of Cardiovascular

Sciences, University of Leicester Introduction: Functional polymorphisms of the endothelial nitric oxide

synthase (eNOS) and methylene tetrahydrofolate reductase (MTHFR) have previously been associated with abdominal aortic aneurysm (AAA) but findings have not been consistent and most analyses have not replicated their results in separate populations. We aim to investigate the association between the MTHFR C677T and eNOS G894T polymorphisms and AAA. Methods: We recruited 358 Caucasian whites from a Mediterranean population who were undergoing elective AAA repair [29 females (8%), mean age: 69 ± 8 years, mean AAA diameter 6 ± 1.4 cm] and 393 individuals (controls) with similar characteristics who did not have an AAA. A second cohort consisting of 400 individuals with an AAA [24 females (6%), mean age: 72 ± 7 years, mean AAA diameter 5.5 ± 1 cm] and 400 controls of predominantly British Caucasian whites was used to replicate findings. Blood samples from both groups were genotyped. Logistic regression analyses were performed, adjusted for established AAA and cardiovascular risk-factors. Results: Genotypes in all groups were in Hardy-Weinberg equilibrium (chisquare). When adjusted for AAA and cardiovascular risk factors the eNOS and MTHFR ‘‘TT’’ alleles were not associated with AAA [p = .35, Odds Ratio (OR): 1.3, 95% Confidence Interval (CI): -.74-2.3 and p = .61, OR: 1.1, CI: 0.7 – 1.9]. Findings were similar in the second (British) cohort [eNOS: p = .90, OR: 1.0, CI: 0.6-1.6 and MTHFR: p = .36, OR: 0.8, CI: 0.5-1.3]. Conclusion: In contrast to previous findings, this study suggests that there is no significant association between these two polymorphisms and AAA. Take-home message: This study suggests that there is no relationship between 2 functional polymorphisms and AAA formation, as thought previously. This provides new insights into the genetics and pathophysiology of AAA.

0138 Kevin Burnand Prize Winner A novel cytosolic protein complex regulates LOX-1 scavenger receptor-mediated endocytosis of proatherogenic oxidised lowdensity lipoprotein particles N. A. Mughal1,2 , K. Freestone2 , Z. Holloway3 , A. P. Monaco3 , D. A. Russell1 , S. Homer-Vanniasinkam1,2 , S. Ponnambalam2

Introduction: The LOX-1 scavenger receptor mediates uptake of oxidised

low-density lipoprotein (OxLDL) particles and regulates atherosclerotic plaque development. Little is known about plasma membrane trafficking of LOX-1-OxLDL complexes from the cell surface to the endosome-lysosome system. We tested the hypothesis that the adaptor protein complexes (AP1AP4) which regulate eukaryote membrane trafficking also regulate this phenomenon. Methods: A yeast-based three-hybrid genetic screen was employed to screen AP1, AP2, AP3 and AP4 for interactions with the LOX-1 cytoplasmic domain. A suitable cell line was identified by immunoblotting for AP abundance. AP expression was investigated in this line using microscopy and staining. Depletion of AP subunit levels using RNA interference tested the requirement for LOX-1-mediated OxLDL endocytosis. Results: This yeast three-hybrid screen revealed that the AP4 complex (but not AP1, AP2 or AP3) interacted with the LOX-1 cytoplasmic domain. Mutation of the LOX-1 endocytosis motif (DDL) on the cytoplasmic domain abrogated this interaction. AP4 levels were low in most cell lines with human epithelial lung carcinoma cells containing the most. The complex showed distribution to intracellular vesicles, Golgi apparatus and the plasma membrane (15-20%). Using epithelial cells transfected to express LOX-1, AP4 showed co-distribution with LOX-1 and OxLDL particles. Depletion of AP4 subunits using RNAi caused a 40-50% decrease in LOX-1-mediated OxLDL endocytosis. Conclusions: These findings suggest that the AP4 cytosolic complex regulates LOX-1-mediated endocytosis and trafficking of OxLDL. This novel pathway thus provides new targets for preventing accumulation of OxLDL particles in vascular tissues for alleviation of cardiovascular disease. Take-home message: AP4 plays a key role in the internalisation of LOX-1-OxLDL complexes. Future targeting of AP4 may provide a new slant on preventing the development and progression of atherosclerotic plaques.

O139 Vein diameter is associated with disease severity not quality of life impairment T. R. A. Lane, A. C. Shepherd, M. S. Gohel, I. J. Franklin, A. H. Davies Academic Section of Vascular Surgery, Imperial College London, Charing Cross Hospital, London, UK Introduction: Symptom assessment in varicose veins is complex, and vein

diameter has been used as a rationing factor for reimbursement by primary care trusts. The aim of this study was to examine the relationship between vein diameter, clinical severity and disease specific quality of life. Methods: Duplex scans from patients with truncal vein reflux awaiting intervention were assessed and maximal vein diameter (VD) recorded. The Aberdeen Varicose Vein Questionnaire (AVVQ), the Venous Clinical Severity Score (VCSS) and clinical CEAP grade was recorded. Results: Data was available for 339 patients, 59% female, 10% obese, mean (SD) age 50 (33–65) and 54.3% C1-C3. The mean AVVQ was 21 (10–32), median (IQR) VCSS 6 (4–8) and clinical CEAP 3 (2–4). Mean (SD) VD was 8.4 mm (4.5-12.3 mm). A weak but significant correlation was found between CEAP and VD (Spearman’s 0.136, p = 0.007), and VD and VCSS (Spearman’s 0.145, p = 0.08). No correlation was found between VD and AVVQ. Male patients had higher AVVQ (p = 0.001) and CEAP (p = 0.026) with a larger VD (p = 0.08). Conclusions: Larger vein diameters were correlated with worse clinical disease severity (CEAP and VCSS) but not with a worse quality of life. Male patients suffered worse clinical severity and quality of life scores. VD >6 mm showed a significantly higher quality of life impairment and clinical severity. Take-home message: Vein diameter indicates clinical severity but not patient experience and symptoms.

1 Leeds Vascular Institute, The General Infirmary at Leeds, Leeds, UK, 2 Endothelial

Cell Biology Unit, Leeds Institute for Genetics, Health & Therapeutics, University of Leeds, UK, 3 Wellcome Trust Centre for Human Genetics, University of Oxford, UK


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O140 The shortfall in survival of patients with repaired thoracic or abdominal aortic aneurysms A. Karthikesalingam, B. O. Patterson, G. Peach, J. D. Poloniecki, A. Vidal-Diez, P. J. Holt, R. J. Hinchliffe, M. M. Thompson St George’s Vascular Institute Introduction: Previous data have shown long-term survival after aneurysm

repair to be poorer than survival in comparable individuals without an aneurysm, largely due to excess cardiovascular mortality. This discrepancy may have been exacerbated by suboptimal management of atherosclerotic risk, and it is not known whether the shortfall persists in contemporary practice. This population study aimed to quantify the current disparity in life expectancy between survivors of aneurysm repair and matched controls. Methods: Patients undergoing repair of abdominal (AAA) or thoracic aortic aneurysm (TAA) from April 2006 to March 2011 were identified from UK Hospital Episodes Statistics. Control subjects were identified who underwent elective inguinal hernia repair, total knee, or total hip arthroplasty with the same date of operation, hospital, age, gender, date of birth, and social deprivation as each AAA/TAA. The primary outcomes were all-cause mortality and adverse cardiovascular events (myocardial infarction, stroke, emergency amputation or limb revascularisation), reported with Kaplan-Meier analysis and compared by log-rank test. Results: 26,976 AAA and 1,404 TAA repairs were identified, with 102,174 and 5,458 controls respectively. Five-year survival was 61% for AAA vs 77% for controls, and 58% for TAA vs 83% for controls (p < 0.001). Freedom from adverse cardiovascular events was 67% for AAA vs 83% for controls and 75% for TAA vs 87% for controls (p < 0.001). Conclusion: Long-term survival after aneurysm repair remains poor and adverse cardiovascular events are common, relative to comparable patients without an aneurysm. A randomised trial of intensive, goal-directed cardiovascular therapy is urgently required to bridge this deficit. Take-home message: Long-term survival after aneurysm repair remains poor and adverse cardiovascular events are common, despite improvements in secondary risk prevention. A randomised trial of intensive, goal-directed cardiovascular therapy is urgently required to bridge this deficit.

ORAL PRESENTATIONS 5B UPPER GI O141 Long term survival following gastrectomy for cancer in randomized controlled oncological trials: Comparison between west and east S. R. Markar1 , A. Karthikesalingam2 , D. Jackson3 , G. Hanna1 1 Department of Surgery and Cancer, St Mary’s Hospital, Imperial College, London, UK, 2 Department of Outcome Research, St George’s Vascular Institute, St George’s Hospital, London UK, 3 MRC Biostatistic Unit, Cambridge, UK

Introduction: The presence of mixed evidence about the value of

lymphadenectomy in gastric cancer surgery coupled with the difference in patients’ demographics and tumour stage between the West and East have doubted the needs to standardise surgical techniques in Western clinical practice. The aim of this study is to compare survival between the West and East following gastrectomy in randomised controlled oncological trials with appropriate adjustment for confounding variables. Methods: Systematic search revealed 25 trials that have randomization into surgery and chemotherapy vs. surgery alone between 1995 and 2012 (n = 7 in East and n = 18 in West). End points were 5-year survival and cancer recurrence. Results: There was association between gastrectomy performed in the East and improved 5-year survival (Pooled OR = 4.83; 95% C.I. = 3.27 to 7.12) and reduced cancer recurrence (Pooled OR = 0.33; 95% C.I. = 0.20 to 0.54). Association of improved 5-year survival with surgery in the East remained


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when meta-regression analysis was performed to adjust for the effect of age, sex, chemotherapy, tumour stage and nodal status and gastrectomy type. Association of reduced cancer recurrence also persisted with meta-regression analysis adjusting for age, chemotherapy, nodal status and gastrectomy type. However there was a reduction in this association when the meta-regression included tumor stage. Conclusions: This analysis shows association between gastrectomy performed in Eastern countries and improved survival. The known difference in surgical techniques between the East and the West is one potential unexamined variable that may be responsible in part for such discrepancy in outcomes. Take-home message: The results of the present study demonstrate that there are factors not explicitly measured in these trials that may be responsible for the improved survival following gastrectomy in the East. The known difference in surgical techniques between the East and the West is one potential unexamined variable that may responsible in part for such discrepancy in outcomes.

O142 Towards molecular assessment of surgical metabolic response: Exhaled breath signatures of major upper gastrointestinal surgery P. R. Boshier, V. Mistry, J. R. Cushnir, O. M. Kon, S. L. Elkin, S. Curtis, N. Marczin, G. B. Hanna Imperial College London Introduction: Breath gas analysis may offer novel insights into the surgical

metabolic response and identify biomarkers of postoperative complications. This study aims to determine the influence of major upper gastrointestinal surgery on exhaled breath metabolite concentrations and the relationship to metabolic stress and lung injury. Methods: Breath samples were collected preoperatively and at 24, 48, 72, 96 and 168hrs following elective transthoracic esophagectomy (n = 25) and gastrectomy (n = 15). Targeted analysis of six prominent breath metabolites was performed by selected ion flow tube mass spectrometry (SIFT-MS). Patients with non-surgical lung injury (community acquired pneumonia) were recruited as positive controls. Results: Perioperative starvation and subsequent reintroduction of nutritional input was associated with significant changes in breath acetone levels. Patients undergoing gastrectomy exhibited significant increases in exhaled acetone during the first 3 days, a response that was not seen following oesophagectomy. In contrast, concentrations of isoprene were significantly elevated in the breath of oesophagectomy patients at postoperative time points 96 (P = 0.023) and 168hrs (P = 0.024). Pneumonia was the most frequent postoperative complications. The concentration of hydrogen cyanide was significantly lower in the breath of patients who developed serious postoperative respiratory complications 72hrs after surgery (13 vs. 4ppb, P = 0.008). Exhaled hydrogen cyanide was also significantly reduced in patients with community acquired pneumonia compared to healthy controls (6 vs. 14ppb, P = 0.001). Conclusions: SIFT-MS can be utilised as a totally non-invasive resource to monitor multiple aspects of metabolic alterations in the postoperative period. Exhaled concentrations of several prominent metabolites are significantly altered following major upper gastrointestinal surgery. Take-home message: Breath gas analysis may offer novel insights into the surgical metabolic response and identify biomarkers of postoperative complications. Exhaled concentrations of several prominent metabolites are significantly altered following major upper gastrointestinal surgery.

O143 A review of the prevalance and impact of anaemia during neoadjuvant therapy for upper gastrointestinal adenocarcinoma B. D. Keeler, J. A. Simpson, M. J. Brookes, A. Reece-Smith, S. Madhusudan, S. Parsons, J. Catton, A. G. Acheson Nottingham University Hospitals NHS Trust

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Introduction: Anaemia is commonly associated with gastrointestinal

Conclusions: HRQL measures are poorly reported with clinical significance

malignancy. The importance of perioperative anaemia is increasingly recognised, with evidence suggesting poorer outcomes in anaemic patients with colorectal cancer independent of allogenic red blood-cell transfusions (ARBT). Advances in management of upper gastrointestinal (UGI) adenocarcinoma have led to increased use of neoadjuvant chemotherapy. These agents can lead to the exacerbation of anaemia, which is not uncommonly identified in these pretreated UGI adenocarcinoma cases. This study aims to review the prevalence of anaemia in patients undergoing neoadjuvant therapy and subsequent resectional surgery for UGI adenocarcinoma. Methods: 73 consecutive patients with oesophageal or gastric adenocarcinoma underwent resectional surgery following neoadjuvant chemotherapy between January 2009 and June 2010. Information was collected from a prospectively updated database and retrospectively from case-notes. Information collected included patient demographics, haemoglobin at diagnosis and perioperatively, and use of ARBT. Anaemia was defined by WHO criteria. Results: There were 64 males (87.6%) 9 females (12.4%), median age 64 years (IQR 58-69y). The prevalence of anaemia at diagnosis was 22%(n = 16), and preoperatively was 69.9%(n = 51). Of the non-anaemic patients at diagnosis (n = 57), 67% became anaemic (n = 38). 20 patients (27%) received ARBT from the day of surgery to fifth postoperative day, of which 18 were anaemic on day of surgery (p = 0.02,). Conclusions: Development of anaemia during neoadjuvant therapy was experienced by a significant number of patients with UGI adenocarcinoma. Patients anaemic at surgery were more likely to require ARBT, highlighting the importance of preoperative treatment of anaemia with iron. Take-home message: Surveillance and treatment of anaemia should be performed for patients undergoing neoadjuvant treatment for oesophageal and gastric malignancy. It commonly develops during treatment, and if not addressed, results in increased red blood cell transfusion administration.

often not discussed. The variety of questionnaires and lack of robust studies meant a meta-analysis of results was not possible. Well designed studies that provide such evidence are needed to inform practice in bariatric surgery. Take-home message: There is a paucity of robust studies reporting health related quality of life measures in bariatric surgery. Well designed prospective studies are needed to inform patients on the outcomes of such surgery.

O144 Health related quality of life reporting in bariatric surgery: A systematic review of current practice T. Abdelrahman1,2 , K. Coulman1,3 , A. Owen-Smith1 , R. C. Andrews4,5 , R. Welbourn3 , J. M. Blazeby1,6 1 School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol, 2 Department of Upper GI Surgery, West Wales General Hospital, Hywel Dda Health Board, Carmarthen, Wales, 3 Department of Bariatric and Upper GI Surgery, Musgrove Park Hospital, Taunton, 4 School of Clinical

Sciences, University of Bristol, Southmead Hospital, Bristol, 5 Department of Diabetes and Endocrinology, Musgrove Park Hospital, Taunton, 6 Division of Surgery, Head & Neck, University Hospitals Bristol NHS Foundation Trust, Bristol Royal Infirmary Introduction: Improvements in health related quality of life (HRQL) are

important indicators of the success of bariatric surgery and should inform clinical decision making. For results of studies to be clinically meaningful, measures of HRQL should be conducted and reported in methodologically robust ways. The aim of this study was to systematically review HRQL reporting in bariatric studies, and focus on the clinical interpretation of these. Methods: Six online databases were searched using specific terms for bariatric surgery and HRQL. Exclusions were: cross-sectional and review articles; analysis of 0.05). The percentage of positive lymph nodes below 5mm was 24.2% and 44.1% for MND and SFB resulting in cancer upstaging (p = 0.037). Conclusions: Lymph node retrieval after gastrectomy depends on pathologist and retrieval method. SFB is associated with higher total and positive lymph node yield than MND and is independent of pathologist. Ignoring small lymph nodes can be a major cause for missing positive nodes and cancer down-staging. Take-home message: Lymph node count is an important qualifier of disease staging and survival prediction in gastric cancer but remains highly variable in Western centers. Systematic fat blocking is associated with higher total and positive lymph node yield than manual nodal dissection and is independent of pathologist.

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