Less common types of mesothelioma
Though most mesothelioma cancers start in the lining of the lungs, called pleural mesothelioma, a quarter of all malignant mesothelioma tumors are found in other parts of the chest or abdomen.1
Ten to 20 percent of mesothelioma cases are mesothelioma of the peritoneum, the lining of the abdominal cavity. Approximately 250 cases are diagnosed each year.2 The cancer is caused by swallowing asbestos fibers after they are breathed in from the air. Symptoms include abdominal pain and swelling, weight loss, anemia, fever and intestinal blockage.3 The best treatment appears to be surgically removing the tumor in combination with chemotherapy.2
A more rare form of mesothelioma is pericardial mesothelioma.3,4 This tumor affects the lining of the heart, called the pericardium. The tumor can constrict the function of the heart, causing chest pain, fluid buildup, difficulty breathing, an irregular heartbeat and persistent cough. Pericardial mesothelioma is usually treated by surgery to remove the cancer, but the disease does not have a good prognosis.
Papillary mesothelioma,5,6 sometimes called well-differentiated papillary mesothelioma (WDPM), is a benign form of mesothelioma, meaning that it does not spread and is not cancerous. The tumor is usually found in the peritoneum of reproductive age women. However, papillary tumors may also arise from the tunica vaginalis in the male reproductive system or the lining of the lungs (pleura).
Papillary mesothelioma usually causes no pain and has a good prognosis. Because this type of tumor is unlikely to spread, it is usually treated by surgically removing the tumor, though many patients experience recurrence. The cause of this tumor has not been definitively linked to asbestos.
Mesothelioma of the tunica vaginalis testis
Mesothelioma of the tunica vaginalis testis3 is the rarest form of malignant mesothelioma. Similar to papillary mesothelioma in men, this cancer arises from the peritoneum around the testes. Only about one-tenth of men with this tumor are younger than 25 years of age — most are over age 50. The symptoms are fluid accumulation in the scrotum or hernia. Prognosis is good after surgical removal of the affected testicle.
When a cancer spreads from one location in the body to another it’s called metastasis. Metastatic mesothelioma7 is the name given to the mesothelioma cancer when it is no longer found in just one place in the body. Any malignant mesothelioma — pleural, peritoneal, pericardial — can spread to another location in the body and become metastatic mesothelioma.
Mesothelioma tends to spread to the lymph nodes,8 but it can also metastasize to the central nervous system9 and other organs. The National Cancer Institute considers metastatic mesothelioma to be part of the advanced stages of the disease.10