How Does Radiation Therapy Work?
High doses of radiation can kill cells or keep them from growing and dividing. Radiation therapy is a useful tool for treating cancer because cancer cells grow and divide more rapidly than many of the normal cells around them. Although some normal cells are affected by radiation, most normal cells appear to recover more fully from the effects of radiation than do cancer cells. Doctors carefully limit the intensity of treatments and the area being treated so that the cancer will be affected more than normal tissue.