Any growth of abnormal cells in the tissue of the brain is known as a tumor. Such growths can be malignant (cancerous) or benign (noncancerous), but because of their proximity to important brain tissue and their enclosure within the skull, both types can be life threatening. Brain tumors are usually classified as low or high grade, depending on how fast they’re growing.

About 52,000 new brain and nervous system tumors are diagnosed every year in the United States, and more than 13,000 people die of brain tumor complications annually. Research has shown that being male, Caucasian, or age 70 or older; being exposed to radiation or toxic chemicals at work; or having a family history of brain tumors increases a person’s risk. Not everyone with these risk factors will get a brain tumor, however, and many people who do develop tumors do not have any of these risks.

Symptoms such as severe morning headaches; nausea or vomiting; changes in speech, vision, or hearing; balance and memory problems; and convulsions may occur when a tumor presses on a nerve or damages a certain area of the brain. The World Health Organization recognizes 126 different types of central nervous system tumors. The following are the most common.

Meningiomas account for 27 percent of tumors that start in the brain. They form in the meninges, the membrane lining the skull, and affect twice as many women as men. Because they rarely spread, they are often curable with surgery. Doctors may prescribe steroids to control swelling and inflammation or may follow a passive strategy known as watchful waiting to monitor the tumor’s growth before considering surgery.

High-grade astrocytomas and glioblastomas originate in the astrocytes, the connective tissue cells of the brain. These tumors grow rapidly, invading nearby folds of the brain, and can be difficult to treat even with surgery, radiation, and chemotherapy. Astrocytomas and glioblastomas account for about 25 percent of all primary brain cancers.

Tumors that begin elsewhere and metastasize, or spread, to the brain are the most common brain tumors, especially since people are surviving primary cancers for longer periods of time.

ADDITIONAL FACTS

  1. Scientists are investigating whether cell phones may cause brain tumors, but no evidence has been found thus far.
  2. After leukemia, brain tumors are the second-most-common type of cancer in children and young adults. Medulloblastoma, for example, is a rare type of tumor that afflicts mainly boys and young men.