Treatment guidelines and techniques in delivery of postmastectomy radiotherapy in management of operable breast cancer.

Abstract

Radiation therapy has been shown to statistically significantly reduce the risk of locoregional recurrence in high-risk patients with operable breast cancer following mastectomy and systemic therapy. Recent trials have also demonstrated a significant survival benefit following radiotherapy in high-risk patients. Therefore, it is important to identify the patients who could potentially derive that survival benefit and to not offer treatment to those patients who are not at increased risk for failure. Established risk factors that predict for increased rates of locoregional recurrence include axillary lymph node involvement and T3 (or T4) disease. While treatment-related factors, such as the extent of the axillary dissection and extent of lymph nodal positivity, also undoubtedly affect locoregional recurrence, additional studies are needed to define the magnitude of their risk. Locoregional patterns of failure have identified the chest wall and supraclavicular/infraclavicular regions to be the most common sites of locoregional failure following mastectomy, which justifies treatment to these regions. While long-term complications are uncommon following locoregional radiotherapy, careful treatment planning is critical to minimize cardiac (and pulmonary) toxicity.