What are the side effects of radiation therapy for breast cancer?

Susan McCloskey, MD
Radiation Oncology
Breast radiation therapy is typically very well tolerated. The most common side effects experienced during a course of breast radiation therapy are fatigue, which is usually mild, and skin coloration changes such as redness, tanning, or darkening of the skin in the radiation field, similar to a sunburn. Radiation therapy is local, focused treatment so you will not feel sick, nauseous, or lose your hair. You may experience mild breast swelling, tenderness, soreness, or intermittent aches and pains in the treatment area. Peeling and blistering of the skin in the radiation field is possible although less common. These side effects are temporary and typically resolve within 2 to 4 weeks after the completion of radiation. Although rare, radiation therapy for breast cancer can be associated with long term side effects. These side effects can include minor changes in the look or feel of the treated breast such as persistent tanning/darkening of the skin in the treatment area; sensitivity to touch in the treatment area; or changes in the size, shape or feel of the treated breast. Risk of long term damage to the heart or lungs is very small with modern radiation therapy techniques. Radiation may add to your risk of developing lymphedema (or swelling of the arm) especially if you are receiving radiation to the surrounding lymph node regions.
When radiation passes through the skin, the skin cells in the treatment area become damaged. If you receive frequent radiation, your skin cells often do not have enough time to repair and regenerate in between treatments.

Thus, common breast cancer radiation side effects may include redness, dryness or irritation of the skin in the treated area. Another common side effect is fatigue, especially in the later weeks of treatment and for some time afterward.

By employing innovative radiation techniques, radiation oncologists are able to deliver higher radiation doses to breast cancer cells while limiting damage to healthy tissue. Your radiation oncologist may also recommend radioprotective drugs, such as amifostine, to help guard healthy tissue from exposure to radiation.

If skin irritation occurs, your doctors will provide various comfort measures. For example, you may receive topical drugs in the form of therapeutic creams or ointments. You may also receive antibiotics to fight infection or pain medications to relieve discomfort. 

Continue Learning about Breast Cancer Treatment

Prophylactic Mastectomy May Have No Benefit
Prophylactic Mastectomy May Have No Benefit
Christina Applegate (2008) and Sharon Osborne (2012) opted for double mastectomies after discovering breast cancer in one breast. They wanted to reduc...
Read More
What should I ask my doctor about breast cancer treatment?
Stuart A. Linder, MDStuart A. Linder, MD
Important questions to ask your breast cancer specialist will include:-Stage and Grade of Tumor-Type...
More Answers
What factors are risks for complications of a lumpectomy?
Columbia University Department of SurgeryColumbia University Department of Surgery
Risks of any surgery are bleeding and infection. Risks specific to lumpectomy include having positiv...
More Answers
What Kind of Treatment Is Needed for Breast Cancer?
What Kind of Treatment Is Needed for Breast Cancer?

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.