Radiation Therapy -- External

Radiation therapy is a treatment for cancer and other diseases. It uses high-energy particles to damage the genetic code (DNA) in the cancer cells. This makes the cells unable to grow or divide. There are two main types of radiation therapy: In certain cases, your doctor may recommend a combination of these. Radiation is often used with other types of treatment, such as surgery, chemotherapy , and immunotherapy (stimulates the immune system to fight infection). This fact sheet will focus on external radiation therapy.

  • Call Your Doctor

    After arriving home, contact your doctor if any of the following occur:

    • Signs of infection, including fever and chills
    • Diarrhea or loss of appetite
    • Unexplained weight loss
    • Frequent urination, particularly if it is associated with pain or burning sensation
    • New or unusual swelling or lumps
    • Nausea and/or vomiting that you cannot control with the medicines you were given
    • Pain that does not go away
    • Unusual changes in skin, including bruises, rashes, discharge, or bleeding
    • Cough, shortness of breath, or chest pain
    • Any other symptom your nurse or doctor told you to look for
    • Any new symptoms

    In case of an emergency, call for medical help right away.

  • Definition

    Radiation therapy is a treatment for cancer and other diseases. It uses high-energy particles to damage the genetic code (DNA) in the cancer cells. This makes the cells unable to grow or divide.

    There are two main types of radiation therapy:

    • External—radiation is delivered by a machine that shoots particles at the cells from outside the body
    • Internal
      —radioactive materials are placed in the body near the cancer cells (also called implant radiation or brachytherapy)


    In certain cases, your doctor may recommend a combination of these. Radiation is often used with other types of treatment, such as surgery,
    chemotherapy
    , and immunotherapy (stimulates the immune system to fight infection).

    This fact sheet will focus on external radiation therapy.

  • What to Expect

  • Reasons for Procedure

    • Control the growth or spread of cancer
    • Attempt to cure cancer
    • Reduce pain or other symptoms caused by cancer (This is called palliative radiation.)

    Radiation therapy is commonly used to treat:

    • Solid tumors such as prostate cancer, breast cancer, and head and neck cancers
    • Lymphomas
      and
      leukemia

  • Possible Complications

    External radiation does not cause your body to become radioactive. It can cause side effects, as the radiation damages your own healthy cells as well as the cancer cells. Common side effects of radiation include, but are not limited to:

    • Fatigue
    • Skin changes (redness, irritation)
    • Reduced white blood cell count
    • Hair loss

    • Nausea, vomiting, or
      diarrhea
    • Appetite loss

    Discuss the specific side effects that you may have with your doctor.

    Factors that may increase the risk of complications include:

    • Previous radiation therapy

    • A personal history of
      lupus
      ,
      scleroderma
      , or
      dermatomyositis

    A woman who is pregnant or could be pregnant should avoid exposure to radiation. It could harm a developing fetus.