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Radiation Therapy

  • Definition

    The use of high-energy rays or particles to treat disease is called radiation therapy.

    Sometimes it is called radiotherapy, x-ray therapy, cobalt therapy, electron beam therapy, or irradiation.


    When radiation is used at high levels (many times those used for x-ray exams) this energy can be used to treat cancer and other illnesses. Special equipment is used to aim the radiation at tumors or areas of the body where there is disease. High levels of radiation can kill cells or keep them from growing and dividing.

    Radiation therapy is a useful tool for treating cancer because cancer cells are growing and dividing more rapidly than many of the normal cells around them. In addition, most normal cells appear to recover more fully from radiation effects than cancer cells. Doctors carefully limit the intensity of treatments and the amount of normal tissue being treated so that the cancer will be harmed more than the patient will.

    About half of all people with cancer are treated with radiation, and the number of cancer patients who have been cured is rising every day. For many patients, radiation is the only kind of treatment needed.

    Thousands of people are free of cancer after having radiation treatments alone or in combination with surgery, chemotherapy, and biological therapy. Doctors can use radiation before surgery to shrink a tumor. After surgery, radiation therapy may be used to stop the growth of any cancer cells that remain.

    In some cases, doctors use radiation along with anticancer drugs to destroy the cancer, instead of surgery. Even when curing the cancer is not possible, radiation therapy is used to shrink tumors and reduce pressure, bleeding, pain, or other symptoms of cancer. This is called palliative treatment.


    How successful is radiation with this type of cancer?

    Will radiation be used in combination with other therapy?

    What type of radiation therapy will you be recommending?

    How often and how long will the radiation need to be given?

    Will any medications be given while receiving radiation therapy?

    How soon will we know if the radiation is successful?

    What side effects might occur during treatment and after treatment?

    How long will the side effects last?