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Side Effects

Side effects are usually temporary and usually go away shortly after treatment ends. Below is a list of possible side effects you might notice during your treatment.
  • Skin irritation similar to a sunburn, sometimes with a peeling reaction toward the end of treatment.
  • Breast swelling can be mild to moderate.
  • Mild tenderness in the breast or chest wall. This will slowly get better over time.
  • Mild fatigue that generally gets better a month or two after treatment ends.

Many of these side effects can be controlled with medications. Tell your doctor or nurse if you experience any discomfort so they can help you feel better.

After the short-term side effects of radiation therapy resolve, others may become noticeable months or years later.

  • Breast firmness or mild shrinkage.
  • Change in skin color and thickness, sometimes fine blood vessels will appear.
  • Scarring of a small part of the lung just under the breast. Generally, no side effects are noticed but rarely radiation may cause a dry cough or shortness of breath that is treatable.
  • Mild decreased range of motion and/or shoulder discomfort.
  • Hand or arm swelling, called lymphedema, can occur but depends upon the extent of surgery and radiation.

Very rare potential side effects include heart injury for left-sided breast cancers and new tumors caused by radiation. Many factors affect your risk for these side effects. Please talk to your radiation oncologist to learn more about how likely these side effects may be for you.