Malignant peritoneal mesothelioma is a form of cancer that affects the peritoneum, which is the lining of the abdomen. It is a rare disease, and it presents in 100 to 500 people a year in the United States. It is also called abdominal mesothelioma, because the peritoneum is the membrane that supports and covers the abdominal cavity, as well as the organs located there. The peritoneal membranes are called visceral and parietal. The visceral refers to the covering of the organs and the parietal refers to the covering of the abdominal cavity.
To further understand mesothelioma we must know that it involves the cells that secrete a lubricating fluid so that the organs can move against each other without friction. These cells make up the mesothelium. When the mesothelium becomes cancerous the cells over-produce fluid. Mesothelioma is usually secondary to the primary source of the malignancy, which is pleural mesothelioma. It is thought that the asbestos fibers may be ingested when swallowed, where they enter digestive tract. It is also believed that the fibers are inhaled into the lungs and transported via the lymphatic system to the abdominal cavity. Cancer cells from the primary source can also become mobile and relocate via the lymphatic system to other areas, this process is called metastasis.
Symptoms of peritoneal mesothelioma are abdominal pain, swelling of the abdomen-which may be caused by fluid retention (acites) or tumor growth-small or large bowel obstruction, anemia-red blood cells below normal level, which causes decreased oxygen levels in the blood, and makes the heart work harder, also causing shortness of breath-weight loss-but you may appear larger around the waist-and fever. If you have been exposed to asbestos in your lifetime and you are having any of these symptoms, you should be evaluated by your physician.
Mesothelioma can be passed on to other people in the family. Spouses who handled dirty clothes to launder them are at risk to having asbestos transferred to them via physical contact with the fibers. Now that more is known about asbestos, workers must change clothes before going home. Special care is taken to limit exposure to the asbestos fibers.
Diagnosis of peritoneal mesothelioma is similar to that of pleural mesothelioma. An x-ray will be taken. Mesothelioma cannot be seen on an x-ray, but a tumor may cause pleural effusion (fluid buildup) which can be seen. The doctor may also order a CT scan or an MRI to back up and add to the findings in the x-ray. Once the scans are done, a biopsy must be done to examine to tissue. The doctor will make a cut through the chest wall; this procedure is called a thoroscopy. This will be done in the hospital under local anesthesia. The doctor may also perform a peritoneoscopy, which is surgically inserting a scope into the abdomen. The procedure is similar for both thoracic and abdominal examinations. Samples of tissue will be obtained for the pathologist to examine under a microscope.
Mesothelioma is quite rare, so if you are diagnosed with it, you should have your doctor help you find a specialist. There is no cure for malignant mesothelioma, but there are treatment options that include surgery, radiation, chemotherapy, and others. The life expectancy of someone with malignant peritoneal mesothelioma varies from person to person. The prognosis depends on how vigorously the cancer is treated and how the patient responds. The patient may live for years, or only for a few months.
Mesothelioma information page