How you prepare

By Mayo Clinic Staff

You'll meet with your radiation therapy team, health care professionals who work together to plan and provide your radiation treatment. Team members usually include:

  • A radiation oncologist, a doctor who specializes in treating cancer with radiation. He or she determines the appropriate therapy for you, follows your progress and adjusts your treatment, if necessary.
  • A radiation physicist and a dosimetrist, who make calculations and measurements regarding your radiation dosage and its delivery.
  • A radiation oncology nurse, who can answer questions about the treatments and side effects, and help you manage your health during treatment.
  • A radiation therapist, who operates the radiation equipment and administers your treatments.

Your radiation oncologist will review your medical history with you and give you a physical exam to check your overall health before you begin radiation therapy. Your oncologist can also discuss the potential benefits and side effects of your radiation therapy.

External radiation therapy

Before your first treatment session, you'll go through a simulation in which a radiation oncologist carefully maps your breast area to pinpoint the precise location of your treatment. During the simulation:

  • A radiation therapist helps you into a position best suited to pinpoint the affected area and avoid damage to surrounding normal tissue. Sometimes pads or other devices are used to help you hold the position.
  • Using a CT scanner, the radiation oncologist locates the treatment area. You'll hear noise from the CT equipment as it moves around you. Try to relax and remain as still as possible to help ensure consistent, accurate treatments.
  • Ink marks or tiny permanent tattoo dots are placed on your skin to guide the radiation therapist in administering the radiation. Be sure not to wash ink marks off until you're told to do so. If the marks can't be seen, you may need to go through the mapping process again.
  • The dosimetrist, radiation physicist and radiation oncologist use computer software to plan the dose of radiation you'll receive. Once the simulation and planning are complete, you can begin treatment. For each session, avoid wearing jewelry, latex bandages, powder, lotion or deodorant on or near your treatment area. These substances can interfere with delivery of the radiation.

Internal radiation therapy

Before internal brachytherapy is started, a special device for the radioactive implants is placed in the area from where the tumor was taken (tumor bed). This may be done during your cancer surgery or as a separate procedure.

If the radiation device is implanted during a separate procedure, it often requires a brief hospital stay. You'll be given local, regional or general anesthetic for the procedure. Once the holder is implanted, you can likely go home.

There are two approaches to internal radiation therapy for breast cancer:

  • Intracavitary brachytherapy. A small, deflated balloon attached to a thin tube (catheter) or a cage of small catheters is inserted in the tumor bed, with the end of the tubes sticking out of the breast. The balloon is filled with saline solution and left in place throughout the course of treatment. That's where the radioactive implants are inserted.
  • Interstitial brachytherapy. Several small catheters are inserted in the breast around the tumor bed to serve as holders for small radioactive pellets. These catheters are generally left in place throughout the course of treatment.
Feb. 13, 2014