What is radiation therapy? When is it used?

Radiation therapy is one of the most common treatments for cancer. It uses high-energy particles or waves, such as x-rays, gamma rays, electron beams, or protons, to destroy or damage cancer cells. Other names for radiation therapy are radiotherapy, irradiation, or x-ray therapy.

Radiation can be given alone or used with other treatments, such as surgery or chemotherapy. In fact, certain drugs are known to be radiosensitizers (RAY-dee-oh-SENS-it-tie-zers). This means they can actually make the cancer cells more sensitive to radiation, which helps the radiation to better kill cancer cells.

There are also different ways to give radiation. Sometimes a patient gets more than one type of radiation treatment for the same cancer.

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master’s-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: June 30, 2015 Last Revised: June 30, 2015

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