Radiation Therapy for Cancer - National Cancer Institute
www.cancer.gov › treatment › typesJan 08, 2019 · Radiation therapy kills cancer cells or slows their growth by damaging their DNA. Credit: National Cancer Institute. Radiation therapy (also called radiotherapy) is a cancer treatment that uses high doses of radiation to kill cancer cells and shrink tumors. At low doses, radiation is used in x-rays to see inside your body, as with x-rays of your teeth or broken bones.