Radiation therapy has some side effects. Some begin during treatment, while others may occur months or years later.
Short-term side effects
During and just after treatment, you may feel tired and your treated breast may be sore. Mild pain relievers such as ibuprofen or acetaminophen can ease breast tenderness.
The treated breast may also be rough to the touch, red (like a sunburn) and swollen. Sometimes the skin may peel, as if it were sunburned. Your radiation oncologist may suggest special creams to ease this discomfort. Sometimes the skin peels further and the area may become tender and sensitive (called a moist reaction). This is most common in the skin folds and the underside of the breast. If this occurs, let your oncologist or nurse know, and he/she can give you creams and pads to make the area more comfortable until it heals.
Most often, side effects from radiation therapy begin within a few weeks of starting treatment and go away within a few weeks after treatment ends .
Nausea is not common with radiation therapy. And, you shouldn’t lose the hair on your head, although there may be some hair loss under the arm or on the breast or chest area receiving radiation (this may be an issue for men with breast cancer).
Learn more about easing pain related to radiation therapy.
Long-term side effects
Over the long-term, you may notice firmness or shrinkage of the breast. You may also have mild tanning of the skin in the treated area. These changes are often permanent.
Women who have axillary lymph nodes removed may develop lymphedema. Lymphedema is a condition in which fluid collects in the arm (or other areas such as the hand, fingers, chest or back), causing it to swell. The chances of getting lymphedema are greater if your treatment includes both :
- Removal of a large number of lymph nodes from the underarm area during breast cancer surgery
- Radiation to the lymph nodes in the underarm area
Learn more about lymphedema.
Rare side effects
Although rare with modern radiation therapy, treatments can injure the normal tissues near the radiation field of the breast or chest wall. Rare side effects include:
- Rib fracture occurs when the radiation weakens the rib cage near the treatment area.
- Heart problems can develop when radiation therapy is given to the left side of the chest.
- Radiation pneumonitis (NOO-moh-NY-tis) is an inflammation of the lungs that can cause shortness of breath, a dry cough and low-grade fever. Severe symptoms can often be relieved by anti-inflammatory drugs. Radiation pneumonitis almost always goes away with time.
- Brachial plexopathy (BRAY-kee-ul pleks-AH-path-ee) can happen when radiation damages nerves in the upper chest. It may cause tingling, pain and weakness in the affected hand and arm that may be temporary or permanent.
These conditions may occur a few months or years after radiation treatment
Radiation therapy and risk of a second cancer
Rarely, radiation treatment can cause a second cancer. The most common cancers that have been linked to radiation therapy are skin cancers and sarcomas (cancers of the connective tissue) [14-16]. However, the risk of a second cancer is very small and is typically far outweighed by the benefits of radiation therapy.