In most cases, the causes of a brain tumor relate to a genetic mutation that results in uncontrolled growth of cells. Chromosomes that regulate the function of a gene and changes inside genes cause the abnormalities. An increased risk of brain tumors is also associated with certain genetic syndromes, but may occur in members of the same family that does not have any suspected genetic conditions.
Metastic cancers travel to the brain from other parts of the body through the blood stream and lymphatic system. Colon cancer, skin cancer (melanoma) lung cancer and breast cancer all are known to cause brain tumors by spreading to the central nervous system.
Race, age and gender seem to play a role as brain tumors occur more frequently in Caucasians, in people of middle-age or older, and in men more than women. Children younger than 9 seem to be at greater risk than other children are. Risk increases for certain types of brain tumors seen repeatedly in the patient’s family history.
Exposure to radiation from treatments for earlier problems may lead to new brain tumors forming as much as 20 to 30 years later. However, no evidence exists of a danger from radio waves, such as that generated by power lines or cell phones.
A higher incidence of brain tumors is seen from chemical exposure and in people who work in oil refining and rubber production; however no direct link has been established.