Peritoneal mesothelioma is a cancer of the lining of the abdomen that is usually caused by exposure to asbestos. Less common than pleural mesothelioma, which attacks the lining of the lungs, peritoneal mesothelioma is the second most common type of mesothelioma affecting about 20 percent of those diagnosed. The term peritoneal refers to the peritoneum, which is a protective lining covering the abdominal organs and the abdominal cavity.
Although there may be other risk factors associated with mesothelioma, like smoking and excessive radiation, the primary risk factor for mesothelioma is exposure to asbestos. Asbestos is a naturally-occurring mineral fiber that was used extensively in construction for almost all of the 20th century due to its strong tensile strength and its resistance to fire and high temperatures. Because it is often easily friable, meaning that it easily crumbles into microscopic airborne particles, the typical exposure to asbestos is inhalation through the lungs, especially with construction or industrial workers that handled asbestos directly. However, asbestos is thought to be conveyed to the abdomen by ingesting food or water that has been exposed to asbestos, or by traveling through the lungs and the lymphatic system into the abdomen. Once in the abdomen, asbestos fibers irritate tissue, cause scar tissue and fluid buildup that can result in cancer cells and malignant tumors.
All types of mesothelioma have a very high latency period, so symptoms often do not manifest themselves until upwards of 40 years after exposure to asbestos. The minimum latency time that has been observed is approximately 15 years. Symptoms might include chest, stomach or abdominal pain. A patient may also have abdominal swelling due to a buildup in fluid, development of lumps, digestive problems, anemia or fatigue.
Diagnosis is often difficult because many of these symptoms can be confused for a number of other potential conditions, so diagnosis cannot be confirmed on the basis of symptoms alone. Typically, X-ray or CT exams are performed to determine visual abnormalities in the abdomen. These are followed up by a biopsy, in which a small amount of tissue or fluid is removed from an area of concern and tested for malignant cells. If the test results for malignancy are positive, further testing could confirm peritoneal mesothelioma cells.
Treatment of peritoneal mesothelioma depends on a number of factors, including the age and overall health of the patient, location of the tumor and, most importantly, the stage to which the tumor has progressed. Doctors usually classify cancers from stage one to stage four depending on how developed the cancer is. Treatment for stage one or stage two diagnosis of peritoneal mesothelioma, in which the cancer is relatively localized and has affected other organs minimally, may be candidates for surgery to remove the tumor, which is then often followed by a combination of chemotherapy and radiation therapy. Patients with later stages may undergo chemotherapy and radiation therapy only. Patients should discuss directly with a doctor the best treatment plans and options for them.