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What Happens During Radiation Therapy for Breast Cancer

What happens during radiation therapy depends on whether you get external beam radiation therapy (EBRT) or internal radiation therapy, which is also called brachytherapy. EBRT is the more common way to have radiation therapy for breast cancer. This is how it works.

After enough time has gone by for your surgery wound to heal (often about two to three weeks), a team of radiation specialists will carefully figure out where to focus the radiation. Then they will mark your body with ink so that they know exactly where to aim the beam of radiation. Usually it's aimed at the whole breast. Sometimes it has to be aimed under your arm and at other parts of your chest, too. It depends on how advanced your cancer is. If you need to lie in an awkward position, the radiologist may make a mold of your body, which can be used to support you and keep you from moving during the treatment.

The treatment itself is like having a regular X-ray, but the radiation is stronger. The treatment lasts only a few minutes and is painless.

In most cases, you'll have to go for radiation five days a week for about six weeks. If you have the more frequent type of radiation, you may have to go to the radiation center twice a day until the treatment is over. If you're getting chemotherapy after your surgery, the doctors may have you wait until the end of chemotherapy to begin your radiation treatments.

For internal radiation therapy, the radiation is directed from inside the body. The radiation therapist places small thin tubes of a radioactive substance directly into the breast where the tumor used to be. In some cases, seeds or pellets of radioactive material may be put into the breast tissue at the tumor site. If your doctor does recommend internal radiation, you'll most likely have it along with or even, in some cases, in place of external radiation. 


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