“Benign” means good (its opposite is malignant). “Tumor” simply means swelling or mass of any kind. A benign tumor is a mass of tissue cells that have grown inappropriately but are not the type of tumor that will erode into adjacent tissues or breakoff and flow into the bloodstream and glands in other places in the body and continue to grow there. Benign tumors often affect the musculoskeletal system and are found in muscle, bone and nerves to name a few. Rarely do these tumors require surgical removal. Occasionally, biopsies will be performed to look at the tissue under the microscope to ascertain for certain that these tumors are benign and not malignant, or cancerous.