Department of Anatomical Pathology, Flinders University,. Bedford Park, SA, Australia ... Royal College of Pathologists Australasia. Thyroid Cytology: Structured ...
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PATHOLOGY 2016 ABSTRACT SUPPLEMENT
at age 18 months, and thought to be a lipomatous haemangioma. Macroscopically it was a smooth, well circumscribed mass composed of fatty tissue intersected by fibrous septa. Microscopically the adipocytes were predominantly mature, merging in some areas with mesenchymal tissue with a loose myxoid background. Definite lipoblasts were not identified. The lesion infiltrated between skeletal muscle fibres in some areas. There was no necrosis, mitotic activity or severe atypia. Appearance was consistent with lipoblastoma/ lipoblastomatosis. Discussion: Lipoblastoma is a rare benign lesion of embryonal white fat, found almost exclusively in infancy and early childhood. It is most commonly located in the extremities (30–70%) and the trunk (20–50%). Lipoblastomas cause symptoms through mass effect, and often exhibit rapid growth. They can be divided into two types: lipoblastoma (70%) which is typically superficial, circumscribed and encapsulated, and diffuse lipoblastomatosis (30%) which are often deeper, poorly circumscribed and infiltrative. 9–25% recur after surgery, and these are largely lipoblastomatosis, while lipoblastoma may mature into lipoma or spontaneously resolve.1 Reference 1. Bruyeer E, Lemmerling M, Poorten VV, et al. Paediatric lipoblastoma in the head and neck: three cases and review of literature. Cancer Imaging 2012; 12: 484–7.
COMPARING EXPECTED RATIOS OF DIAGNOSTIC CATEGORIES OF THYROID FINE NEEDLE ASPIRATES AT FLINDERS MEDICAL CENTRE (FMC); USING OLD REPORTING SYSTEMS VERSUS THE NEW RCPA RECOMMENDED AUSTRALASIAN SYSTEM G. Kelly, A. Kruger, S. Klebe Department of Anatomical Pathology, Flinders University, Bedford Park, SA, Australia Background: The RCPA has recently published new Australasian guidelines for thyroid cytology reporting in order to provide a standardised approach. The new system, based on a framework of the Bethesda system, aims to be practical, reproducible and provide relevant guidance to clinicians on management options. Aims: To assess if ratios of categories of thyroid biopsies using the new Australasian guidelines are the same as those recorded using older systems of classification. Methods: All thyroid FNA biopsies reported from Flinders Medical Centre between July 2012 and July 2015 were retrieved from the Delphic database and analysed using Microsoft Excel. Results and discussion: Of 387 biopsies reviewed, most (63%) were assessed as RCPA Category 2/Benign, 11% as Category 1, 5% as Category 3, 6% as Category 4, 2% as Category 5 and 3% as Category 6. Findings largely matched the expected proportions of biopsies quoted to fall in each category by the 2014 RCPA Protocol.1 These results support the continued use of the new Australasian guidelines at FMC. Reference 1. Royal College of Pathologists Australasia. Thyroid Cytology: Structured Reporting Protocol. 1st Edition 2014. Sydney: RCPA, 2014.
Pathology (2016), 48(S1)
PIGMENTED SQUAMOUS CELL CARCINOMA Louise Killen, A.O. Said, Svetlana Cherepanoff Sydpath, St Vincent’s Hospital Sydney, and Narrabri Hospital, NSW, Australia We present an interesting case of a pigmented squamous cell carcinoma. A 75-year-old male presented with a recurrent squamous cell carcinoma (SCC) on the right cheek. Histopathological examination showed a CK5/6 positive acantholytic SCC infiltrating the reticular dermis, in which benign melanocytes were seen to be colonising the tumour. Pigment was seen in CD68 positive melanophages. The benign, colonising melanocytes showed strong diffuse positivity for HMB45 and MART1, and strong focal staining for SOX10. The tumour was diagnosed as a pigmented SCC. Pigmented SCCs are relatively rare tumours and are estimated to comprise between 0.01 to 7% of all squamous cell carcinomas, according to English literature.1 They frequently present clinically as a rapidly evolving crusted papule on sun-damaged skin.2 Histologically, they consist of a proliferation of atypical keratinocytes and bland dendritic melanocytes and melanophages.1 The differential diagnosis of pigmented SCCs is broad and includes benign entities such as melanoacanthoma, malignancies such as melanoma with overlying pseudoepitheliomatous hyperplasia, and biphasic tumours such as squamomelanocytic tumour. It is important to distinguish pigmented SCCs from these differential diagnoses, as this will have significant bearing on the patient’s prognosis. References 1. Satter EK. Pigmented squamous cell carcinoma. Am J Dermatopathol 2007; 29: 486–9. 2. Pigmented squamous cell carcinoma Morgan MB, Lima-Maribona J, Miller RA, et al. Pigmented squamous cell carcinoma of the skin: morphologic and immunohistochemical study of five cases. J Cutan Pathol 2000; 27: 381–6.
PNEUMOCYTOMA: MAKING THE DIAGNOSIS OF A RARE BENIGN PULMONARY NEOPLASM WITH THE AID OF CYTOLOGY PREPARATION IN AN INTRAOPERATIVE CONSULT Nicholas Wee Chong Koh, Cristine Szu Lyn Ding, Clarence Hai Yi Teo Department of Pathology, Tan Tock Seng Hospital, Singapore Pneumocytoma is a rare benign pulmonary neoplasm that is often found on thoracic imaging in asymptomatic patients. Accurate diagnosis is vital to prevent additional extensive surgical resection. We describe such a case in a 40-year-old female who presented with a right lung nodule incidentally discovered on a screening chest X-ray. Further clinical evaluation revealed two nodules in the right lung. Both lung nodules were sent for intraoperative consultation and a final diagnosis of pneumocytoma and adenocarcinoma in situ, respectively, was made. A summary of the clinical and pathological findings as well as a discussion of the issues pertaining to the diagnosis of pneumocytoma, in particular focusing on the cytological and intra-operative features, is presented.