Late Toxicity of Radiotherapy: A Problem or a Challenge for the Radiation Oncologist?

BACKGROUND: Large randomized clinical trials have established radiotherapy in conjunction with adjuvant systemic treatment as standard treatment in breast cancer after both mastectomy and lumpectomy. Although standard radiation therapy is well tolerated by the majority of patients, some patients might suffer from late normal tissue effects. METHODS: The literature on radiotherapy following surgery of breast cancer was reviewed with regard to late toxicity. RESULTS: Radiotherapy may, to some degree, cause persistent pain in the breast, arm and shoulder in up to 30-50% of patients after 3-5 years, lymphedema in 15-25%, and restriction of arm and shoulder movement in 35%. Awareness of cardiotoxicity is needed since anthracyclines, trastuzumab, and radiotherapy may cause damage to the heart. However, using modern radiotherapy techniques, the available evidence does not suggest a higher incidence of cardiac mortality. CONCLUSIONS: This review updates the database on toxicity from radiation in breast cancer. Advances in research of radiation-induced late effects may lead to improved treatment choices for breast cancer patients including radiotherapy and may improve quality of life after surviving breast cancer.