Peritoneal cancer: a rare type of cancer that begins in the lining tissue of the abdomen, known as the peritoneum. Because cancers that develop in other organs may sometimes spread to this site, cancer that begins in the peritoneum itself are referred to as primary peritoneal cancers. Peritoneal cancer is similar to ovarian cancer in its appearance and behavior. Early signs of peritoneal cancer, like those of ovarian cancer, may be non-specific and hard to identify. After symptoms develop, they often resemble those of ovarian cancer and include abdominal pain or bloating, abdominal pressure, loss of appetite, a feeling of fullness in the abdomen, feeling full after even a small amount of food consumption, weight changes, and abnormal vaginal bleeding.
Although peritoneal cancer is similar to ovarian cancer, it can develop in both men and women. However, women are more likely than men to get peritoneal cancer, and women at risk for ovarian cancer (such as those who have inherited a BRCA gene mutation) are at increased risk for peritoneal cancer. In women, peritoneal cancer can develop even after the ovaries have been surgically removed. Older age is another risk factor for the condition.