Risk factors

In most people with primary brain tumors, the cause of the tumor isn't clear. But doctors have identified some factors that may increase your risk of a brain tumor.

Risk factors include:

• Exposure to radiation. People who have been exposed to a type of radiation called ionizing radiation have an increased risk of brain tumor. Examples of ionizing radiation include radiation therapy used to treat cancer and radiation exposure caused by atomic bombs.
• Family history of brain tumors. A small portion of brain tumors occurs in people with a family history of brain tumors or a family history of genetic syndromes that increase the risk of brain tumors.