You may also hear it referred to as x-ray therapy, cobalt therapy, or irradiation. Radiation therapy is an effective way to treat many kinds of cancer in almost any part of the body. About half of all patients with cancer are treated with radiation. For some, radiation therapy is the only treatment necessary. For others, radiation therapy is combined with other treatments, such as surgery and chemotherapy, to best treat their cancer.
Radiation works best against cells that are growing and dividing.
Because cancer cells grow and divide more rapidly than many of the normal cells around them, radiation therapy is a useful tool in treating cancer. Although some of the healthy cells in the area where the radiation is given are also destroyed, most normal cells tend to recover more quickly and more fully from the effects of radiation than do the cancer cells. Careful planning is taken to ensure that the radiation affects as little of the normal tissue as possible. Radiation therapy can be given either externally or internally. Most patients who receive radiation therapy receive it externally.