Causes of Brain Tumors
The cause of most brain cancers is unknown. In general, cancers are due to a combination of inherited genetic factors coupled with some exposure during life, such as exposure to a chemical, a virus or radiation. Of these, the best case has been made for exposure to high doses of radiation, such as those given as part of cancer treatment, and an increased risk of subsequent brain cancer. Exposure to some chemicals in the workplace has also been found to increase the risk of developing brain cancer. Infections may play a role as well: the virus that causes mononucleosis, the Epstein-Barr virus, has been linked to an increased risk of a form of lymphoma that affects the central nervous system, CNS lymphoma, which also is more common among individuals infected with HIV, the virus that causes AIDS. Genetics play a particularly important role in a number of brain tumors that are clearly linked to a number of inherited disorders and disorders due to chromosome damage. Genetic damage that accumulates as we age can also trigger changes in cells that lead to brain cancer. But, again, in most cases the cause for an individual patient’s brain cancer cannot be identified.