Breast cancer - radiation therapy; Carcinoma of the breast - radiation therapy; External beam radiation - breast; Intensity-modulated radiation therapy - breast cancer; Radiation - whole breast; WBRT
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.
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.
There are several ways the doctor and therapists may place little marks on your skin that can help make sure the radiation is pointed at the cancer but not at healthy tissue.
- Some centers use ink tattoos. These marks are permanent but are most often smaller than a mole. These cannot be washed off and you can bathe and shower normally. After treatment, if you want the marks removed laser or surgery can be used.
- Some centers use marks that can be washed off. You may be asked not to wash the area during treatment and the marks may need to be touched up before each treatment session.
During each treatment session:
- You will lie on a special table, either on your back or your stomach.
- The technicians will position you so the radiation targets the treatment area.
- Sometimes alignment x-rays or scans are taken before treatment to make sure you are lined up in the right treatment position.
- Some centers use a machine that delivers radiation at certain points of your breathing cycle. This can help limit radiation to the heart and lungs. You may be asked to hold your breath while the radiation is being delivered. You may have a mouthpiece to help regulate your breathing.
- Most often, you will receive radiation treatment for between 1 and 5 minutes. Each day you will be in and out of the treatment center in less than 20 minutes on average.
Why the Procedure Is Performed
After surgery, cancer cells may remain in the breast tissue or lymph nodes. Radiation can help kill the remaining cancer cells. When radiation is delivered after surgery is performed, it is called adjuvant (additional) treatment.
WBRT may be given:
- For ductal carcinoma (DCIS)
- For stage I or II breast cancer, after lumpectomy or partial mastectomy (breast-conserving surgery)
- For more advanced breast cancer, sometimes even after full mastectomy
- For cancer that has spread to local lymph nodes (in the neck or armpit)
- For widespread breast cancer, as a palliative treatment to relieve symptoms
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:
- You may develop some breast swelling, tenderness, and sensitivity.
- Your skin over the treated area may turn red or darker in color, peel, or itch (much like a sunburn).
Most of these changes should go away about 4 to 6 weeks after the radiation treatment is over.
Your provider will explain care at home during and after radiation treatment.
Late (long-term) side effects may include:
- Decreased breast size
- Increased firmness of breast
- Skin redness and discoloration
- Swelling in the arm (lymphedema) in women who have had nearby lymph nodes removed
- In rare cases, rib fractures, heart problems (more likely for left breast radiation)
- Development of a second cancer in the treatment area (the breast, ribs, or muscles of the chest or arm)
WBRT following breast-conserving surgery reduces the risk of cancer coming back and of death from breast cancer.
Alluri P, Jagsi R. Postmastectomy radiotherapy. In: Bland KI, Copeland EM, Klimberg S, eds. The Breast: Comprehensive Management of Benign and Malignant Diseases. 5th ed. Philadelphia, PA: Elsevier; 2018:chap 49.
National Cancer Institute website. Breast cancer treatment (Adult) (PDQ) - health professional version. www.cancer.gov/types/breast/hp/adult/breast-treatment-pdq. Updated October 11, 2019. Accessed October 16, 2019.
National Cancer Institute website. Radiation therapy and you: support for people who have cancer. www.cancer.gov/publications/patient-education/radiation-therapy-and-you. Updated October 2016. Accessed August 2, 2018.