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Breast Cancer Health Center

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Radiation Therapy for Breast Cancer

This treatment uses high levels of radiation to kill cancer cells or keep them from growing and dividing. Because it targets the disease, it minimizes damage to healthy cells.

Will I Need Radiation?

Your doctor may recommend it after a lumpectomy (a breast-preserving surgery to remove a tumor) or after a mastectomy to lower the odds of the cancer returning in that breast.

You may also have radiation to treat some symptoms of advanced cancer.

Treatments generally start several weeks after surgery, so your body has some time to heal. If your doctor recommends chemotherapy too, you might start chemo first.

What Types of the Therapy Might My Doctor Recommend?

External beam radiation is most commonly used to treat breast cancer. A machine outside your body aims a beam of radiation on the area affected by the disease.

Brachytherapy delivers radiation to the cancer through something implanted in your body.

What to Expect With External Beam Radiation

Your therapist will escort you into the treatment room and help you get in the right position. Then she'll leave the room and start the treatment.

It's important to hold still and stay relaxed. Cameras and an intercom allow the therapist to see and hear you. Tell her right away if you're concerned about something.

The therapist will be in and out of the room to reposition the machine and your body. The machine won’t touch you, and you won’t have any pain during the treatment.

Your therapist verifies you're in the right position by taking an X-ray called a "port film" on your first day of treatment and every week thereafter. These films don't show how your cancer is responding.

Why Are There Marks on My Skin?

Small marks that look like freckles are tattooed on your skin along the treatment area when you have external beam radiation. They give your medical team an outline of that area. 

Don’t try to wash these marks off or retouch them if they fade. The therapist will re-mark the treatment area when needed.

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