Overview of Nervous System Tumors
A tumor is the abnormal, spontaneous growth of new tissue. Tumors are either benign (do not spread to other tissues or parts of the body) or malignant (cancerous tumors that invade other tissues and parts of the body). Nervous system (NS) tumors can develop in either the brain or spinal cord, although spinal cord tumors are rare.
Benign tumors and cancerous tumors at the site of origin are referred to as primary tumors. Tumors that develop somewhere other than the site of origin are called a metastatic tumors.
More than 100,000 people in the United States are diagnosed with a brain tumor each year, and the numbers are increasing. In most cases, the cause for the brain tumor is unknown. Because of the incredible complexity of the human brain and its role in the normal function of the body, brain tumors often have incapacitating consequences.
Surgery and radiation are the most common treatments for brain tumors, although the effectiveness of these treatments may be limited by the risk for damage to healthy brain tissue.
About 44 percent of all primary brain tumors are benign. Although these tumors do not spread, they are serious, can recur after they have been removed, and can be fatal.
Malignant brain tumors are the second leading cause of cancer death in young adults under the age of 34, young children under the age of 15, and people over the age of 65.