The most common type of the cancer is malignant pleural mesothelioma, which affects the pleura — the mesothelial membrane lining the lungs and chest wall.
Mesothelioma that begins in the pleura typically results from asbestos fibers being inhaled. Tumors that develop in the pleura may spread to the nearby diaphragm, heart, and blood vessels of the chest. Early symptoms of malignant pleural mesothelioma can include shortness of breath, pleural effusion (pleural fluid build-up), chest pain, cough, and a lack of energy.
Although the cancer can spread (“metastasize”) from the pleura into the lung, the origin site is the actual pleural tissue surrounding the lung – not the lung itself. (There are many differences between mesothelioma and lung cancer.)
When it develops in the peritoneum, the mesothelial membrane that covers the abdominal cavity and the organs within it, the cancer is called peritoneal mesothelioma (or abdominal mesothelioma).
Peritoneal mesothelioma is the second-most common form of this cancer, accounting for about 10 percent to 15 percent of new diagnoses.
Peritoneal mesothelioma may result from swallowing asbestos fibers or inhaling fibers that then work their way into the abdomen.
Patients with malignant peritoneal mesothelioma often experience abdominal swelling due to fluid build-up accompanied by abdominal pain, weight loss, and loss of appetite.
The pericardium is the mesothelial membrane covering the heart.
Pericardial mesothelioma is a highly lethal and very rare form of the cancer, accounting for roughly 1 percent to 5 percent of all new mesothelioma cases.
Fluid in the pericardial space, shortness of breath, fever, chest pain, weight loss, and heart palpitations are symptoms of pericardial mesothelioma.
The rarest of all types, mesothelioma of the tunica vaginalis testis (testicular mesothelioma) is a tumor of the membrane covering the testicle.
Because of its rarity, there is little clinical agreement about testicular mesothelioma characteristics and symptoms, making diagnosis extremely difficult.
Patients sometimes report painful swelling of the testicle, and a doctor diagnoses the cancer intra-operatively (during surgery) or post-operatively, following laboratory analysis.
Ultrasound and other imaging scans and tests may also be used for testicular mesothelioma diagnosis.