Abstract: |
Neoadjuvant chemotherapy (NAC) is commonly used in patients with locally advanced breast cancer. Several challenges faced by radiation oncologists in treating these patients include the lack of an accurate pathologic stage to guide management and determining how response to NAC should affect further local therapy. In the postmastectomy setting, the available data demonstrates that both initial clinical stage and final pathologic stage independently predict for locoregional recurrence (LRR). Postmastectomy radiation therapy (PMRT) improves local control in patients with locally advanced clinical stage III disease, regardless of response to NAC, and in those with residual pathologic nodal disease. Patients with early-stage disease who respond well to NAC are at low risk for LRR. Within the intermediate risk groups, additional factors such as molecular subtype and presence of a complete pathologic response, both of which have been shown to predict for LRR, may help guide further management decisions. With regard to breast-conserving therapy after NAC, the available data demonstrates this is a safe and effective option in patients with minimal up-front nodal disease and small residual tumors after NAC. Additional contraindications for lumpectomy in any setting should also be considered. The role of regional nodal irradiation in patients who have received NAC is controversial, particularly among pathologically nodenegative patients. There are two ongoing randomized trials open for accrual in the USA that aim to evaluate the benefits of adjuvant radiation therapy, including regional nodal irradiation, after NAC. © Springer Japan 2016. |