In situations where the cancerous cells have spread, surgeons sometimes must remove large areas of healthy tissue along with the tumor to insure that no malignancy remains. In these cases, physicians remove lymph nodes from the tumor area because cancer can spread through nodes. If removing all the lymph nodes does not eliminate the malignancy, physicians combine some surgical procedures with either chemotherapy or radiation therapy to kill any malignancy that may remain after surgery. Physicians use radiation therapy to destroy cancer cells. Ironically, radiation can cause and destroy cancer.
Health workers administer radiation in several different ways.
Sometimes, they inject it into the bloodstream, where it circulates throughout the body, finding the cancer and destroying it. In other cases, they implant radioactive capsules directly into the tumor. The most common form of radiation therapy is machine radiation, which focuses a small beam of radiation directly at the tumor. Radiation kills all the cancer cells in the beam's focus. The radiation beam goes through the body and the tumor, without killing all the cells along its path.