Types of Mesothelioma

Mesothelioma is a cancer of the mesothelial cells. These cells are located on the outer layers of tissue that line the internal organs. The lining helps organs with movement inside the body.

Mesothelioma is usually only found in those that have encountered asbestos, which is a cancerous substance. Asbestos was used in many industries in the past. Breathing in the dust of asbestos can cause any of the many types of mesothelioma even decades after exposure.

Mesothelioma types are classified based on the cell type of the tumor and its location. There are three main types of mesothelioma are epitheliod, sarcomatiod and mixed/biphasic. The most common form of the disease, epithelial mesothelioma is found in 50% to 70% of cases. This form of mesothelioma occurs when the cancer originates in the epithelial cells within the tissues around the internal organs.

Sarcomatous mesothelioma occurs when cancerous tumors begin in the fibrous membranes or tissues of the mesothelial lining. This form of mesothelioma makes up 7% to 20% of cases. Mixed or biphasic mesothelioma occurs when a both epithelial and sarcomatous involvement are discovered. The second most common form of the disease, mixed/biphasic mesothelioma makes up 20% to 35% of cases. Sometimes, it may be hard to diagnose mesothelioma as it can resemble other cancers.

Mesothelioma can also be classified by the location of the original tumor. The disease commonly develops in the pleura, which is the tissue membrane enclosing the lungs. Approximately 70% to 80% patients develop mesothelioma in the pleura. Mesothelioma can also develop in the abdomen, or the peritoneum. In approximately 10% to 20% of mesothelioma cases, the cancer can be found in the peritoneum. This is the second most common region where mesothelioma develops. Peritoneal mesothelioma occurs when the cancerous tumor forms in the membranes lining the abdominal organs. Mesothelioma can also develop in the membrane lining the heart, though pericardial mesothelioma is uncommon.