CT findings and serum ca 125 levels in malignant peritoneal mesothelioma: report of 11 new cases and review of the literature

Abstract

The aim of this study was to review and reappraise the clinical and CT features of malignant peritoneal mesothelioma (MPM), and to discuss differential diagnosis. The history, clinical, and laboratory data, and imaging studies of 11 patients with a histologically proven diagnosis of MPM, were retrospectively reviewed. Our patients consisted of 7 women and 4 men, with a median age of 48 years (age range 40-55 years). There was a definite history of significant asbestos exposure in 6 patients. Abdominal swelling (9 of 11) was the most common presenting symptom. The mean serum CA-125 (normal value 1.2-32 U/ml) level was 230 U/ml (range 19-1000 U/ml). The most common radiological findings were extensive or moderate amounts ascites (11 of 11), irregular or nodular peritoneal thickening (11 of 11), omental involvement (10 of 11), mesentery involvement (9 of 11), pleural thickening, plaques or calcification (7 of 11), pleural effusion (6 of 11), and bowel wall thickening (5 of 11). Two patients had large upper abdominal masses. Computed tomography findings of MPM are nonspecific and inadequate to pinpoint specific diagnosis. The diagnosis requires histological demonstration which is commonly made by an image or laparoscopic-guided biopsy. Pleural changes suggesting asbestosis combined with CT findings and high CA-125 levels can suggest, but are not diagnostic of, mesothelioma. Suggesting the diagnosis of MPM is important because histological and immunohistochemical tests are needed for diagnostic accuracy.

CT differentiation of diffuse malignant peritoneal mesothelioma and peritoneal carcinomatosis

“…Kebapci M et al 19 reported smooth thickening (36%) and irregular thickening (64%) in MPM. Charoensak A et al 6 reported smooth thickening (13.9%) and irregular thickening (48.8%) in PC.…”

“…The pleated appearance shows soft tissue thickening of the leaves of the mesentery. In prior studies, the mesentery was involved in 9 of 11 DMPM patients, 19 while it was involved in 20 patients of 53 PC patients. 6 Similarly, 18 DMPM patients (37.5%) showed thickening of the mesentery, while only four PC patients (8.51%) showed thickening of the mesentery in our study.…”

Prognostic factors influencing survival in 35 patients with malignant peritoneal mesothelioma

“…Calcified plaques are less frequent in MPM than in pleural mesothelioma, but calcified pleural plaques and other signs associated with asbestos exposure may exist in the chest in up to 50% of patients with MPM [20]. In a previously published study, pleural changes, such as calcification or thickening, were found in a high proportion (65%) of patients with MPM [21]. In the present study, radiological evaluation revealed evidence of pleural calcification/plaques in 51% of the patients and pleural thickening in 20%, which is in accordance with the literature.…”

Malignant peritoneal mesothelioma: a review

“…Most of the research on serum markers have been done in pleural mesothelioma, with some patients shown to have elevations in CA-125, alpha fetoprotein, CEA, mesothelin, osteopontin, and fibulin-3. Unfortunately, their sensitivities are too low to be used for diagnostic purposes (28,(33)(34)(35). Levels of serum mesothelinrelated protein (SRMP) have shown more promise, with a sensitivity of 60% (7,36).…”

“…The lack of a primary site with neither lymph node involvement nor distant metastases helps differentiate MPM from other intra-abdominal malignancies (27). Ascites is found in 60-100% of patients that are newly diagnosed (28,29). Other findings include caking, thickening or masses in the omentum, mesenteric nodules, peritoneal thickening, diaphragmatic involvement, scalloping of the intraabdominal organs such as the liver and spleen, and loculated ascites (30,31).…”