CT of peritoneal mesothelioma: analysis of eight cases

In order to define the computed tomographic appearance of mesothelioma, eight patients with histologically proven peritoneal mesotheliomas had computed tomography (CT) performed during the course of their disease. CT findings for all cases were analyzed for evidence of tumor involvement in the peritoneum, mesentery, liver, bone, lymph nodes, and lower pleural space, and for ascitic and pleural fluid. CT findings included evidence of peritoneal involvement (7/8 patients, 88%), ascites (6/8, 75%), mesenteric involvement (6/8, 75%), pleural involvement (4/7, 57%), bone destruction (2/8, 25%), peritoneal mass (1/8, 12%), and retroperitoneal lymph node involvement (1/8, 12%). On the basis of diffuse mesenteric and peritoneal involvement and high incidence of ascites, CT may suggest the diagnosis of peritoneal mesothelioma; however, it may be difficult to differentiate from carcinomatosis, gastrointestinal malignancies, ovarian carcinomas, and, rarely, lymphomas. It is important to suggest the diagnosis of peritoneal mesothelioma because special stains and electron microscopy are necessary for pathologic diagnosis. Experience suggests that CT may be useful in suggesting the diagnosis and biopsy site, and after response to therapy of peritoneal mesothelioma.