Primary brain tumors begin in the brain itself or in surrounding tissues, such as the brain-covering membranes (meninges), cranial nerves, pineal gland, or pituitary gland. When normal cells mutate, they grow and divide at increased rates, resulting in a mass of abnormal cells, which form a tumor.
Most brain tumors are not linked with any known risk factors. However, there are a few factors that can raise the risk.
Making healthier lifestyle changes (i.e. quitting drinking and smoking) can help reduce the risk of many cancers in adults, including lung and breast cancers. Regarding brain tumors, however, there are no known lifestyle-related or environmental risk factors other than radiation exposure.