Mesothelioma

Peritoneal mesothelioma is a form of mesothelioma, a cancer of the lining of the abdominal cavity. It is less common than the pleural form of mesothelioma, comprising approximately one-fifth to one-third of the total number of mesothelioma cases diagnosed. According to the SEER (Surveillance, Epidemiology, and End Results) database, these diagnoses are approximately 54.7 per cent male versus 45.3 per cent female, with the median age being 65-69.

The most clinical symptoms at the time of presentation may include abdominal pain, abdominal mass, increased abdominal girth, distention of the abdomen, ascites (fluid in the abdomen), fever, weight loss, fatigue, anemia and digestive disturbances. Some patients sometimes complain of more non-specific symptoms for a number of months prior to a confirmed diagnosis. In a percentage of cases, peritoneal mesothelioma is found incidentally when the patient has sought help for another health problem such as gallbladder, hernia or pelvic mass.

As with all mesotheliomas, the diagnosis of peritoneal mesothelioma can be difficult for some doctors. CT findings may help differentiate between the two clinical types of peritoneal mesothelioma, termed “dry” or “wet”, since their appearances are very different upon imaging. In the “dry” type, CT may reveal multiple small masses or a single dominant localized mass. There is normally little or no ascites. In the “wet” type, CT may reveal widespread small nodules, but no dominant mass. Ascites is usually present.

If fluid is present, it may be removed in a procedure called paracentesis. Unfortunately, as is the case with pleural mesothelioma, fluid analysis offers limited diagnostic value. It is normally a tissue biopsy obtained in a laproscopic exploratory that will yield a definitive diagnosis.