Diagnosis and management of patients with malignant peritoneal mesothelioma.

Malignant peritoneal mesothelioma (MPM) is a rare neoplastic condition that arises, usually diffusely, from the serosal membranes of the abdominal cavity. MPM represents about 7% to 10% of all mesothelioma diagnoses and this translates into approximately 800 cases per year in the United States. The disease has variable tumor biology but progression, when it occurs, is almost always within the abdominal cavity. Although many patients can be successfully treated at initial presentation, the disease is almost always fatal in time. It afflicts men and women almost equally and the median age at presentation is 50 years. The diagnosis is made when a diffuse malignant process within the abdominal cavity is observed and a tissue sample reveals the characteristic histopathology and immunohistochemical profile of mesothelioma. Initial staging is usually via a cross sectional imaging study of the abdomen and pelvis making sure that the lower thorax is also assessed. If the disease burden and distribution is favorable then operative exploration, cytoreduction, and hyperthermic intraperitoneal chemotherapy (HIPEC) are considered first line treatment in selected patients. Systemic pemetrexed and cisplatin (or gemcitabine) have modest response rates that are of limited duration. Research advances with novel systemic or intraperitoneal agents hold promise.