John A. Spencer, MD, FRCR Sarah E. Swift, MRCP, FRCR Nafisa Wilkinson, MA, MRCPath Andrew P. Boon, MD, FRCPath Geoffrey Lane, MD, MRCOG Timothy J. Perren, MD, FRCP Index terms: Computed tomography (CT), guidance, 791.12112, 791.12115 Peritoneum, biopsy, 791.1261 Peritoneum, neoplasms, 791.32, 791.33 Ultrasound (US), guidance, 791.12985 Published online: September 18, 2001 10.1148/radiol.2203010070 Radiology 2001; 221:173–177 1 From the Departments of Clinical Ra- diology (J.A.S., S.E.S.), Pathology (N.W., A.P.B.), and Gynaecology (G.L.) and the Imperial Cancer Research Fund Cancer Medicine Research Unit (T.J.P.), St James’s University Hospital, Beckett St, Leeds LS9 7TF, England. Received No- vember 29, 2000; revision requested January 11, 2001; revision received March 12; accepted March 22. J.A.S. supported by a Pump Priming Grant from the Royal College of Radiologists. T.J.P. supported by the Imperial Cancer Research Fund. Address correspon- dence to J.A.S. (e-mail: wilsonspencer @compuserve.com). © RSNA, 2001 Author contributions: Guarantor of integrity of entire study, J.A.S.; study concepts, J.A.S., T.J.P., G.L., N.W.; study design, J.A.S., N.W.; litera- ture research, J.A.S., S.E.S., N.W., T.J.P., G.L.; clinical studies, G.L., T.J.P.; data acquisition, J.A.S., N.W., A.P.B., S.E.S.; data analysis/interpretation, J.A.S., S.E.S., N.W.; manuscript preparation, J.A.S., S.E.S., N.W.; manuscript definition of in- tellectual content, J.A.S., N.W., T.J.P.; manuscript editing, revision/review, and final version approval, all authors. Peritoneal Carcinomatosis: Image-guided Peritoneal Core Biopsy for Tumor Type and Patient Care 1 PURPOSE: To assess image-guided peritoneal core biopsy for the diagnosis of tumor type and treatment of patients with peritoneal carcinomatosis. MATERIALS AND METHODS: Thirty-five women (age range, 47– 85 years; mean age, 69 years) prospectively identified in a gynecologic oncology center underwent 18-gauge core biopsy in omental cake (n = 25), peritoneal (n = 7), or adnexal (n = 3) sites. No complications of biopsy occurred. Standard hematoxylin-eosin analysis of the biopsy cores was supplemented by immunohistochemical markers to CA-125, carcinoembryonic antigen, cytokeratin 7, and cytokeratin 20. Diagnoses were vali- dated with further multidisciplinary review, subsequent surgery, and response to specific chemotherapy. RESULTS: In 27 (77%) of the 35 women, a confident primary site diagnosis was obtained with standard hematoxylin-eosin analysis of core biopsy material from the following sites: ovary (n = 22), breast (n = 2), colon (n = 2), and lymphoma (n = 1). The finding at hematoxylin-eosin analysis in another seven (20%) women was poorly differentiated adenocarcinoma with no definite primary site but with an immunohistochemical profile suggesting ovarian cancer (CA-125 positive, carcino- embryonic antigen negative, cytokeratin 7 positive, cytokeratin 20 negative). There was one false-negative biopsy result. CONCLUSION: Image-guided peritoneal core biopsy with hematoxylin-eosin anal- ysis supplemented with immunohistochemical analysis is a simple, safe, and accu- rate technique for providing site-specific diagnoses in women with undiagnosed peritoneal carcinomatosis. The most common cause of peritoneal carcinomatosis in women is ovarian cancer. Two-thirds of women with ovarian cancer present with abdominal dissemination of disease, the standard management of which comprises surgical debulking followed by chemotherapy (1). It is now recognized that surgery, even in the most expert hands, is unlikely to achieve optimal debulking in some patients with very widespread peritoneal disease. Other patients with advanced disease are not candidates for major cytoreductive surgery. As a result, and as supported by findings of a study by the European Organisation for Research and Treatment of Cancer (2), the recent tendency has been to treat such patients with a number of cycles of primary (neoadjuvant) chemotherapy, with the aim of achieving substantial cytoreduction, and to follow this with interval debulking surgery and further cycles of chemotherapy. However, most experts regard this approach as experimental; therefore, it is the subject of further investigation in ongoing randomized clinical trials, including the Gynecologic Oncol- ogy Group Protocol 152 in the United States and the OVO6 study by the Medical Research Council in the United Kingdom. In this protocol, women may be randomly assigned to receive standard treatment with primary surgery followed by chemotherapy or with neoadjuvant chemotherapy followed by interval debulking surgery. Prior to commencing chemotherapy, optimal management should include a firm histologic diagnosis to confirm the clinical, radiologic, and biochemical diagnoses of ovarian cancer. Metastatic breast or gastrointestinal cancer may clinically, radiologically, and even biochem- 173