Which types of tumors are benign?

Cannot spread.: Tumors are collections of cells that multiply, creating "growths" or "lumps". Tumors may be benign or malignant. A benign tumor lacks the ability to spread to other parts of the body. A malignant tumor ("cancer") may break away from the organ where it developed and travel through the bloodstream or lymphatic circulation and take over other organs. We perform biopsies to differentiate the two.

Not CA, can get big: Cancers (malignant) tumors lose normal control with other cells, have unrestricted growth; they can enlarge, spread by blood or lymph. Can be fatal. Benign tumors are abnormal, but not cancers. Can get big, but don't spread by blood or lymph. Generally not fatal, although benign brain tumors can cause a lot of trouble-not much room to spare in the skull.