Your radiation oncologist will explain the possible side effects of radiation therapy for cancer, including uncommon side effects that may involve the heart and chest area.

Fatigue is a common side effect, especially in the later weeks of treatment and for several weeks afterward. Rest is important, but health professionals usually advise you to try to stay reasonably active, matching your activities to your energy level.

The skin in the treated area may become red, dry, tender, and itchy. Toward the end of treatment, the skin may become moist and "weepy." These effects are temporary, and the area will gradually heal when treatment is completed. Expose the area to air as much as possible to help the skin heal. Some types of clothing may rub the skin and cause irritation, so you may want to wear loose-fitting cotton clothes. Women may need to find an alternative to wearing a bra while the skin heals.

Good skin care is important during radiation therapy, and you should check with your health professional before using any deodorants, lotions, or creams on the treated area. The effects of radiation therapy on the skin are temporary, and the area gradually heals once treatment is over. You may notice a slight change in the color of the skin.

You may also develop radiation esophagitis, an irritation of the esophagus that can develop after a few weeks of radiation treatment, especially if you also are receiving cancer medicines (chemotherapy). The esophagitis generally goes away within a month after radiation treatment is completed.

Uncommon side effects of radiation therapy may involve the heart, lungs, or ribs and include a cough, shortness of breath, or chest pain.

Serious long-term side effects are rare but may include problems with lung function or an increased susceptibility to heart problems.

For women, the breast in the radiated area may:

• Feel firmer or heavier.
• Be larger because of fluid buildup or smaller because of tissue changes.
• Be more sensitive or less sensitive.

Most side effects of radiation go away when treatment is over, but some may not.