Whole breast radiation therapy


Whole breast radiation therapy (WBRT) uses high-powered x-rays to kill breast cancer cells.

Cancer cells multiply faster than normal cells in the body. Because radiation is most harmful to quickly growing cells, radiation therapy damages cancer cells more than normal cells. This prevents the cancer cells from growing and dividing, and leads to cell death.

Alternative Names

Breast cancer - radiation therapy; Carcinoma of the breast - radiation therapy; External beam radiation - breast; Intensity-modulated radiation therapy - breast cancer; Radiation - whole breast; WBRT


This type of radiation is delivered by an x-ray machine that targets radiation either to the whole breast, or the chest wall (if done after mastectomy). Sometimes, radiation will also target the lymph nodes in the armpit or neck area or under the breast bone.

You may receive radiation treatment either in a hospital or in a private outpatient radiation center. You will go home after each treatment. A typical course of treatment is given 5 days a week for 3 to 6 weeks. Each treatment is scheduled the same time each day for your convenience.

Before you have any radiation treatment, you will meet with the radiation oncologist. This is a doctor who specializes in radiation therapy.

During each treatment session:

Why the Procedure Is Performed

Radiation is used to prevent breast cancer from coming back in the breast, chest wall, or lymph nodes in the neck or the armpit area. When radiation is delivered after surgery is performed, it is called adjuvant (additional) treatment.

Whole breast radiation therapy may be given:

Before the Procedure

Tell your health care provider what medicines you are taking.

Wear loose-fitting clothes to the treatments.

You are not radioactive after radiation treatments. It is safe to be around others, including babies or children. As soon as the machine stops, there is no more radiation in the room.

After the Procedure

Radiation therapy, like any cancer therapy, can also damage or kill healthy cells. The death of healthy cells can lead to side effects. These side effects depend on the dose of radiation and how often you have the therapy.

Side effects can develop early during treatment (within a few weeks) and be short-lived, or they may be more lasting long-term side effects. Late side effects can happen months or years later.

Early side effects 1 to 3 weeks after your first treatment may include:

Most of these changes should go away about 4 to 6 weeks after the radiation treatment is over.

Your health care provider will explain care at home during and after radiation treatment.

Late (long-term) side effects may include:

Outlook (Prognosis)

WBRT following breast-conserving surgery reduces the risk of cancer coming back and of death from breast cancer.


National Cancer Institute. Breast cancer treatment (PDQ). Cancer.gov Web site. Updated August 11, 2016. www.cancer.gov/types/breast/hp/breast-treatment-pdq. Accessed September 13, 2016.

National Cancer Institute. Radiation therapy and you: support for people who have cancer. Cancer.gov Web site.www.cancer.gov/publications/patient-education/radiation-therapy-and-you. Accessed September 13, 2016.

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