Radiation therapy is a treatment used for cancer and, less commonly, thyroid disease, blood disorders, and noncancerous growths. It can have a targeted, powerful effect on tumors that are confined to a specific area. Radiation can form part of curative or palliative treatments against tumors.
Radiation therapy is the use of high-energy radiation to damage cancer cells' DNA and destroy their ability to divide and grow. It may be delivered using machines called linear accelerators or via radioactive sources placed inside the patient on a temporary or permanent basis.