Incorporating Risk Factors to Identify the Indication of Post-mastectomy Radiotherapy in N1 Breast Cancer Treated with Optimal Systemic Therapy: A Multicenter Analysis in Korea (KROG 14-23)

In a recent meta-analysis, post-mastectomy radiotherapy (PMRT) reduced any first recurrence (AFR) and improved survival in N1 and N2 patients. We investigated risk factors for AFR in N1 after optimal systemic therapy without PMRT, to define a subgroup of patients who may benefit from PMRT