To review CT appearance of peritoneal carcinomatosis underlying some typical aspects ... peritoneum (mesothelioma) or extraperitoneal organs (breast cancer).
Imaging of Peritoneal Carcinomatosis with MDCT: spectrum of diagnostic patterns, sites involved and proposal for a new detailed reporting scheme. Award:
Magna Cum Laude
Poster No.:
C-2078
Congress:
ECR 2012
Type:
Educational Exhibit
Authors:
M. Ciolina, P. Baldassari, M. Iannitti, A. Pichi, F. Iafrate, A. Laghi; Rome/IT
Keywords:
Pathology, Contrast agent-intravenous, CT, Education, Abdomen
DOI:
10.1594/ecr2012/C-2078
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Learning objectives To define Peritoneal Carcinomatosis and to briefly review its pathogenesis, the modalities in which peritoneal metastases spread, the importance of peritoneal boundaries, of peritoneal spaces and peritoneal fluid circulation. To review CT appearance of peritoneal carcinomatosis underlying some typical aspects and sites that radiologists have to check to make a detail report. To propose a new reporting scheme.
Background Definition: Peritoneal Carcinosis is defined as seeding and implantation of neoplastic cells into peritoneal cavity and may represents the advanced evolutive stage of every tumors developed into abdominal and pelvic organs. However ovarian, stomach and colorectal cancers accounts for almost all case 1-2. Furthermore, there are also tumors, even though rare, that develop directly from peritoneum (mesothelioma) or extraperitoneal organs (breast cancer). When the disease increases, the tumoral cells reach and affect the membrane covering the same organs (visceral peritoneum). Once this "barrier" has been passed, the affected cells are able to move into the abdominal cavity, carried by the peritoneal fluid. These cells tend to accumulate in those points of greater liquid readsorption, creating agglomerates that grow more and more, spreading into the whole abdomen and originating the carcinosis.
Peritoneal metastases spread When neoplastic cells reach peritoneal cavity, they continue to spread in four possible routes 3-5:
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(1) Direct spread along peritoneal ligaments, mesenteries and omenta to non-contiguous organs; (2) Intraperitoneal seeding via ascitic fluid; (3) Lymphatic extension; (4) Embolic haematogenous spread.
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Fig. 1 References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Intraperitoneal seeding via ascitic fluid is one of the most important way of peritoneal metastases spreading and the main cause of peritoneal carcinomatosis. Peritoneal fluid circulation The peritoneal cavity is subdivided by peritoneal reflections and mesenteric attachments into several compartments and recesses that are anatomically continues, either directly or indirectly 3-5.
Fig. 2: Peritoneal cavity is subdivided into several spaces and recesses by peritoneal reflections and mesenteric insertions. References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY
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Fig. 3: Force of gravity drives pool of peritoneal fluid preferentially in pelvic cavity. In particular, from the left infracolic space, flow is direct along the superior plane of sigmoid mesocolon and than along the right side of the rectum. From the right infracolic space spread occurs along the small bowel mesentery. The cul-de-sac is first filled and then, symmetrically, the lateral paravesical recesses. From the pelvis peritoneal fluid is able to flow upward due to the pressure gradient created by diaphragm during inspiration and peristaltic motion of the intestine. Fluid enters the paracolic gutters and then moves into the right subhepatic and right subphrenic regions. The left paracolic gutter is shallow and is limited superiorly by the phrenicocolic ligament, which extends from the splenic flexure of the colon to the diaphragm. Consequently, the majority of fluid flows into the right paracolic gutter.
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References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Images for this section:
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Fig. 1
Fig. 2: Peritoneal cavity is subdivided into several spaces and recesses by peritoneal reflections and mesenteric insertions.
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Fig. 3: Force of gravity drives pool of peritoneal fluid preferentially in pelvic cavity. In particular, from the left infracolic space, flow is direct along the superior plane of sigmoid mesocolon and than along the right side of the rectum. From the right infracolic space spread occurs along the small bowel mesentery. The cul-de-sac is first filled and then, symmetrically, the lateral paravesical recesses. From the pelvis peritoneal fluid is able to flow upward due to the pressure gradient created by diaphragm during inspiration and peristaltic motion of the intestine. Fluid enters the paracolic gutters and then moves into the right subhepatic and right subphrenic regions. The left paracolic gutter is shallow and is limited superiorly by the phrenicocolic ligament, which extends from the splenic flexure of the colon to the diaphragm. Consequently, the majority of fluid flows into the right paracolic gutter.
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Imaging findings OR Procedure details
CT imaging of peritoneal carcinomatosis Peritoneal Carcinosis is characterized by the presence of neoplastic implants with different morphological features and distribution in peritoneal cavity (6-10). Radiologist should evaluate: 1. Morphology 2. Localization Morphological aspects: There are three board categories: Solid implants Cystic implants Mixed implants
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Fig. 4: Different aspects of peritoneal implants. A) Axial contrast enhanced CT scan showing solid implants (arrow) presenting as several homogenous soft tissue nodules; B) Intraoperative image of solid implants (circle). C) Coronal contrast enhanced CT image showing a cystic implant (arrow) over small bowel loops appearing hypodense due to the internal fluid component. D) Intraoperative image of cystic implants (circle). E Axial contrast enhanced CT image showing a 4 cm implant of peritoneal carcinomatosis (arrow) presenting an ovular shape and a mixed structure consisted of a mucinous cystic component and a solid irregular rounded wall showing contrast enhancement. F Intraoperative image of mixed implants (circle). References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY In all types of categories calcifications can be present or not.
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Fig. 5 References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Solid, cystic and mixed implants can present with different patterns that depicts typical aspects of peritoneal carcinomatosis (10). Micronodular Pattern Micronodular pattern is characterized by the presence of tiny 1-5 mm milky spots of peritoneal implants diffusely involving the tunica serosa and subserosal fat. Greater omentum, lesser omentum and mesentery are typically involved.
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Fig. 6: Micronodular Patter: a)and c) CT axial images showing several 4-5 mm implants involving great omentum and mesentery. b) Surgical specimen of mesentery. References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Nodular Pattern Nodular pattern is characterized by the presence of > 5 mm nodular implants diffusely involving the tunica serosa and subserosal fat . Nodules may have an oval shape with rounded contours or a star shape appearence with spiculated margins providing a stellate pattern.
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Fig. 7: a) Axial CT image showing a stellate nodule over ascending colon. References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Omental cake Omental cake consists of a diffuse nodular involvement of the greater omentum in association with fibrotic tissue. This leadis to a consolidation of the omental fat that seems to be stratified.
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Fig. 16: Omental Cake: a) CT axial image showing diffuse great omentum involvement b) Surgical specimen References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Plaque like pattern This aspect is typically found in subdiaphragmatic spaces and is due to the confluence of multiple nodular implants. Plaques are irregular soft-tissue thickenings of inconstant extension that coat abdominal viscera and peritoneal walls presenting a lower attenuation than the parenchyma on contrast-enhanced scans.
Fig. 8: "Plaque like" implant: a) Axial contrast enhanced CT image showing a "plaque-like" implant (arrow) over hepatic surface appearing relatively hyopdense in comparison with surrounding parenchyma, due to the presence of a mucinous component.b) Surgical intervention confirms the plaque like implant (arrowhead).
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References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Mass like pattern Mass like pattern is typically found in pelvis and comes out from the same mechanism of 'plaque like' appearance. In this case, the confluence of multiple nodular implants can lead to the formation of tissue mass which can reach sizes of several centimeters. When an individual masses are about 10 cm in diameter or larger it is called "bulky tumor".
Fig. 9: "Mass like" implant: a) Axial contrast enhanced CT image showing a large inhomogeneous soft tissue mass (arrow) located in left iliac fossa. b) Surgical intervention confirms the bulky malignant mass. References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Teca aspect Small bowel loops appear completely enveloped by a thickened layer of visceral peritoneum that covers the bowel loops as a sleeve. Sometimes neoplastic tissue that completely coated small bowel loops causes small bowel obstruction with consequent dilatation of proximal loops, a condition called "ileal freezing".
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Fig. 10: Teca Aspect: a) CT coronal image b)CT axial image c) CT axial image showing small bowel loops completely coated by a thickened visceral peritoneum. Neoplastic tissue produces small bowel obstruction with consequent dilatation of proximal loops, a condition called "ileal freezing". d) Surgical specimen. References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Neoplastic Ascitis Ascites may be due to increased capillary permeability and fluid production or to obstructed lymphatic vessels and decreased absorption. During inspiration fluid accumulates in sub- diaphragmatic spaces, paracolic gutters and epiploon retrocavity. In some cases, also in advanced stages, there is only few ascitis or it is absent.
Fig. 11 References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY
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Localization of peritoneal carcinomatosis Radiologists must specify every sites of peritoneal carcinomatosis in order to provide a staging as detailed as possible. The best rule to make a good report is to carefully check the surface of the bodies covered by the peritoneal layer, peritoneal ligaments and peritoneal spaces that surround them. The most common sites involved by peritoneal carcinomatosis will now be considered dividing abdomen in upper-mesocolic space, infra-mesocolic space and pelvis and considering also retropertoneal space, subperitoneal space and subcutaneus metastases.
Uppermesocolic space:
Fig. 12
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References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY
Fig. 13 References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Inframesocolic space:
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Fig. 14 References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY
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Fig. 15 References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Pelvis:
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Fig. 17 References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY
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Fig. 18 References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Subcutaneus tissue ("Sister Mary Joseph's Nodule") and Retroperitoneal space:
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Fig. 20: A patient with pancreatic adenocarcinoma(arrowhead) presented with multiple cystic implants in subcutaneus tissue(white arrow), called siter Mary Joseph's nodule, and retroperitoneal implants (blue arrow). References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Subperitoneal space:
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Fig. 21: Multiple cystic implants of carcinomatosis (arrow) inside mesorectum, in a patient with rectal mucinous adenocarcinoma. References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Reporting Scheme
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Fig. 19 References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY Images for this section:
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Fig. 4: Different aspects of peritoneal implants. A) Axial contrast enhanced CT scan showing solid implants (arrow) presenting as several homogenous soft tissue nodules; B) Intraoperative image of solid implants (circle). C) Coronal contrast enhanced CT image showing a cystic implant (arrow) over small bowel loops appearing hypodense due to the internal fluid component. D) Intraoperative image of cystic implants (circle). E Axial contrast enhanced CT image showing a 4 cm implant of peritoneal carcinomatosis (arrow) presenting an ovular shape and a mixed structure consisted of a mucinous cystic component and a solid irregular rounded wall showing contrast enhancement. F Intraoperative image of mixed implants (circle).
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Fig. 5
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Fig. 6: Micronodular Patter: a)and c) CT axial images showing several 4-5 mm implants involving great omentum and mesentery. b) Surgical specimen of mesentery.
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Fig. 7: a) Axial CT image showing a stellate nodule over ascending colon.
Fig. 16: Omental Cake: a) CT axial image showing diffuse great omentum involvement b) Surgical specimen
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Fig. 8: "Plaque like" implant: a) Axial contrast enhanced CT image showing a "plaquelike" implant (arrow) over hepatic surface appearing relatively hyopdense in comparison with surrounding parenchyma, due to the presence of a mucinous component.b) Surgical intervention confirms the plaque like implant (arrowhead).
Fig. 9: "Mass like" implant: a) Axial contrast enhanced CT image showing a large inhomogeneous soft tissue mass (arrow) located in left iliac fossa. b) Surgical intervention confirms the bulky malignant mass.
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Fig. 10: Teca Aspect: a) CT coronal image b)CT axial image c) CT axial image showing small bowel loops completely coated by a thickened visceral peritoneum. Neoplastic tissue produces small bowel obstruction with consequent dilatation of proximal loops, a condition called "ileal freezing". d) Surgical specimen.
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Fig. 12
Fig. 13
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Fig. 14
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Fig. 15
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Fig. 17
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Fig. 18
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Conclusion Pretreatment approach to Peritoneal Carcinomatosis requires an accurate staging with detailed information about number of implants and sites involved. Knowledge of patterns of peritoneal carcinomatosis and sites most frequently involved is crucial for radiologists. A reporting scheme is necessary to lead report and description of disease.
Fig. 19 References: M. Ciolina; Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, Rome, ITALY
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Personal Information References 1. Levy AD, Shaw JC, Sobin LH. Secondary tumors and tumorlike lesions of the peritoneal cavity: imaging features with pathologic correlation. Radiographics. 2009 Mar-Apr;29(2):347-73. 2. Levy AD, Arnáiz J, Shaw JC, Sobin LH. Primary peritoneal tumors: imaging features with pathologic correlation. RadioGraphics 2008;28:583-607. 3. Meyers MA, Oliphant M, Berne AS, Feldberg MA. The peritoneal ligaments and mesenteries: pathways of intraabdominal spread of disease.Radiology. 1987 Jun;163(3):593-604. 4. Meyers MA. Distribution of intra-abdominal malignant seeding: dependency on dynamics of flow of ascitic fluid.Am J Roentgenol Radium Ther Nucl Med. 1973 Sep;119(1):198-206. 5. Meyers MA. Dynamic radiology of the Abdomen. Springer-Verlag.1976 pp 37-71. 6. Dromain C, Leboulleux S, Auperin A, Goere D, Malka D, Lumbroso J, Schumberger M, Sigal R, Elias D. Staging of peritoneal carcinomatosis: enhanced CT vs. PET/CT.Abdom Imaging. 2008 Jan-Feb;33(1):87-93. 7. Kim SJ, Kim HH, Kim YH, Hwang SH, Lee HS, Park do J, Kim SY, Lee KH. Peritoneal metastasis: detection with 16- or 64-detector row CT in patients undergoing surgery for gastric cancer.Radiology. 2009 Nov;253(2):407-15. Epub 2009 Sep 29. 8. Coakley FV, Hricak H. Imaging of peritoneal and mesenteric disease: key concepts for the clinical radiologist. Clin Radiol. 1999 Sep;54(9):563-74.
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9. Walkey MM, Friedman AC, Sohotra P, Radecki PD. Ct manifestation of peritoneal carcinomatosis. AJR 150:1035-1041,1988 10. Iafrate F, Ciolina M, Sammartino P, Baldassari P, Rengo M, Lucchesi P, Sibio S, Accarpio F, Di Giorgio A, Laghi A. Peritoneal carcinomatosis: imaging with 64-MDCT and 3T MRI with diffusion-weighted imaging. Abdom Imaging. 2011 Oct 5.
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