Risks

Side effects from radiation therapy differ significantly depending on the type of treatment and which tissues are treated. Side effects tend to be most significant toward the end of your radiation treatment. After your sessions are complete, it may be several days or weeks before side effects clear up.

Common side effects during treatment may include:

• Mild to moderate fatigue
• Skin irritation, such as itchiness, redness, peeling or blistering, similar to what you might experience with a sunburn
• Breast swelling

Depending on which tissues are exposed, radiation therapy may cause or increase the risk of:

• Arm swelling (lymphedema) if the lymph nodes under the arm are treated
• Damage or complications leading to removal of an implant if you had breast reconstruction with an implant after mastectomy

Rarely, radiation therapy may cause or increase the risk of:

• Rib fracture or chest wall tenderness
• Inflamed lung tissue or heart damage
• Secondary cancers, such as bone or muscle cancers (sarcomas) or lung cancer