Also called: Benign neoplasms, Noncancerous tumors

Tumors are abnormal growths in your body. They are made up of extra cells. Normally, old cells die, and new ones take their place. Sometimes, however, this process goes wrong. New cells form even when you don't need them, and old cells don't die when they should. When these extra cells form a mass, it is called a tumor. Tumors can be either benign or malignant. Benign tumors aren't cancer. Malignant ones are. Benign tumors grow only in one place. They cannot spread or invade other parts of your body. Even so, they can be dangerous if they press on vital organs, such your brain. Treatment often involves surgery. Benign tumors usually don't grow back.