A brain tumor is an abnormal growth of tissue in the brain. Unlike other tumors, brain tumors spread by local
Each year, more than 17,000 brain tumors are diagnosed in the United States. About half of all primary brain tumors are benign, but in life-threatening locations. The rest are malignant and invasive.
Benign brain tumors, composed of harmless cells, have clearly defined borders, can usually be completely removed, and are unlikely to recur. Benign brain tumors do not infiltrate nearby tissues but can cause severe pain, permanent brain damage, and death. Benign brain tumors sometimes become malignant.
Malignant brain tumors do not have distinct borders. They tend to grow rapidly, increasing pressure within the brain (IICP) and can spread in the brain or spinal cord beyond the point where they originate. It is highly unusual for malignant brain tumors to spread beyond the central nervous system (CNS).
Primary brain tumors originate in the brain. They represent about 1% of all cancers and 2.5% of all cancer deaths.
Approximately 25% of all cancer patients develop secondary or metastatic brain tumors when cancer cells spread from another part of the body to the brain. Secondary brain tumors are most apt to occur in patients who have:
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Author Info: Rosalyn Carson-DeWitt M.D., The Gale Group Inc., Gale, Detroit, Gale Encyclopedia of Medicine, 2002 |