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Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells.
Cancer cells multiply faster than normal cells in the body. Because radiation is most harmful to quickly growing cells, radiation therapy damages cancer cells more than normal cells. This prevents the cancer cells from growing and dividing, and leads to cell death.
Radiation therapy is used to fight many types of cancer. Sometimes, radiation is the only treatment needed. It may also be used to:
TYPES OF RADIATION THERAPY
External beam radiation is the most common form. This method carefully aims high-powered x-rays or particles directly at the tumor from outside of the body.
Internal beam radiation is placed inside of your body.
SIDE EFFECTS OF RADIATION THERAPY
Radiation therapy can also damage or kill healthy cells. The death of healthy cells can lead to side effects.
These side effects depend on the dose of radiation, and how often you have the therapy. External beam radiation may cause skin changes, such as hair loss, red or burning skin, thinning of skin tissue, or even shedding of the outer layer of skin.
Other side effects depend on the part of body receiving radiation:
Zemen EM, Schreiber EC, Tepper JE. Basics of radiation therapy. In: Niederhuber JE, Armitage JO, Doroshow JH, et al., eds. Abeloff's Clinical Oncology. 5th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2013:chap 27.
National Cancer Institute. Radiation therapy and you: support for people who have cancer. Available at: http://www.cancer.gov/cancertopics/coping/radiation-therapy-and-you. Accessed May 29, 2014.
Reviewed By: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.