Radiation therapy

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Radiation therapy is the use of high-dose X-rays to destroy cancer cells and shrink tumors. Radiation may come from a machine outside the body (external radiation therapy) or from the placement of thin plastic tubes containing radiation (radioisotopes) into the area where the cancer cells are found (internal radiation therapy, or brachytherapy).

Radiation therapy is standard treatment for many types of cancer. It may be used in combination with surgery, chemotherapy, or hormonal therapy.




The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.