Radiation therapy

Radiation therapy

Radiation therapy is used to fight many types of cancer. Radiation targets rapidly dividing cells like cancer cells. Radiation prevents cell division and the replication of DNA (the genetic building blocks).

Also known as: Therapy - radiation and Radiotherapy

Definition

Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells.

Information

Cancer cells multiply faster than normal cells in the body. Because radiation is most harmful to rapidly growing cells, radiation therapy damages cancer cells more than normal cells. Specifically, radiation therapy damages the DNA of cancer cells. Doing so prevents the cancer cells from growing and dividing. Unfortunately, certain healthy cells can also be killed by this process. The death of healthy cells can lead to side effects.

Radiation therapy is used to fight many types of cancer. It is often used to shrink a tumor as much as possible before surgery. Radiation can also be given after surgery to prevent the cancer from coming back.

For certain types of cancer, radiation is the only treatment needed. Radiation treatment may also be used to provide temporary relief of symptoms, or to treat cancers that cannot be removed with surgery.

There are two forms 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 uses radioactive seeds that are placed directly into or near the tumor. Internal beam radiation is also called interstitial radiation or brachytherapy.

The following are some commonly used radioactive substances:

  • Cesium (137Cs)
  • Cobalt (60Co)
  • Iodine (131I)
  • Phosphorus (32P)
  • Gold (198Au)
  • Iridium (192Ir)
  • Yttrium (90Y)
  • Palladium (103Pd)

Radiation therapy can have many side effects. These side effects depend on the part of the body receiving radiation, the dose of radiation, and how often you have the therapy.

  • Hair loss
  • Skin pain
  • Red, burning skin
  • Shedding of the outer layer of skin (desquamation)
  • Increased skin coloring (hyperpigmentation)
  • Thinning of skin tissue (atrophy)
  • Itching
  • Fatigue and malaise
  • Low blood counts
  • Difficulty or painful swallowing
  • Edema (swelling of skin and soft tissues)
  • Changes in taste
  • Loss of appetite
  • Nausea
  • Vomiting
  • Increased susceptibility to infection

Radiation therapy can be harmful to a developing baby in the womb during pregnancy.

References

Perry MC. Principles of cancer therapy. In Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 192.

See also:

  • Disease

    Osteonecrosis

    Aseptic necrosis

    Osteonecrosis is bone death caused by poor blood supply to the area. It is most common in the hip and shoulder.

  • Surgery

    Stereotactic radiosurgery

    Stereotactic radiosurgery is a form of radiation therapy that focuses high-powered x-rays on a small area of the body. With regular radiation therapy treatment, the healthy tissue nearby also receives radiation. Stereotactic radiosurgery better focuses the radiation on the abnormal area. ...

  • Special Topic

    Proton therapy

    Proton therapy is a kind of used to treat cancer. Like other types of radiation, proton therapy kills cancer cells and stops them from growing.

Review date:
June 2, 2010
Reviewed by:
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
Copyright Information A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2008 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.