Asbestos exposure is the main cause of mesothelioma. After these fibers are breathed in, they travel to the ends of small air passages and reach the pleura where they damage mesothelial cells. This leads to inflammation and scarring as well as stimulating the growth of these cells. The fibers may also damage DNA (the genetic 'blueprint" in each cell) and cause changes that result in uncontrolled cell growth. If swallowed, these fibers can reach the abdominal cavity where they have a role in causing peritoneal mesothelioma.

It is still not known whether infection with the SV40 virus increases the risk of mesothelioma, or exactly how it might do so. In lab studies, researchers have found that the virus can affect certain genes that have been linked with cancer, but further research in this area is needed.

Last Medical Review: 03/17/2009
Last Revised: 03/17/2009