Postmastectomy locoregional radiotherapy: is it here to stay?

Postmastectomy radiotherapy (PMRT) clearly reduces the risk of locoregional recurrence for patients with invasive breast cancer with involved axillary lymph nodes. For many years it has been controversial whether or not it also decreases the risks of distant failure and, ultimately, death due to cancer, especially for patients receiving systemic therapy. There is now clear evidence that PMRT confers such benefits. However, published series vary substantially in describing the incidence of locoregional failure (LRF) following mastectomy with regards to particular patient subsets (such as those defined by the number of involved axillary nodes). Details of surgery and systemic therapy also affect this risk. This chapter will review the available data on these subjects, as well as their interpretation and clinical use. Much remains uncertain with regards to the benefits of PMRT in specific situations. Nonetheless, it appears that PMRT is indeed "here to stay." Semin Oncol 28:245-252.