Peritoneal mesothelioma is a tumor of the peritoneum membrane. This thin membrane of mesothelial cells surrounds and protects many of the organs in the abdomen. Asbestos exposure is the only known cause of peritoneal mesothelioma in the U.S. However, it can take decades before initial symptoms of this disease appear, and accounts for about one-fifth of all mesotheliomas.
While peritoneal mesotheliomas are less common than pleural mesotheliomas, they tend to be more invasive, and thus result in a shorter life expectancy for the patient. Mesotheliomas have also been found in the stomach and other abdominal organs.
Like all cancers, peritoneal mesothelioma can be either benign or malignant. Even though symptoms of peritoneal mesothelioma take years to develop, it is sometimes diagnosed by mere coincidence and before any symptoms actually appeared.