Recurrence-free survival in a multinational noninferiority trial of omitting axillary dissection in breast cancer with sentinel-node metastases

The multinational noninferiority SENOMAC trial randomized patients with clinically node-negative primary T1 to T3 breast cancer and one or two sentinel lymph node (SLN) macrometastases (> 2 mm in largest dimension) 1:1 to axillary lymph node dissection (ALND) or SLN-biopsy (SLNB) only. Radiation therapy including nodal target volumes was administered to 89.9% of the SLNB group and 88.4% of the ALND group. The median duration of follow-up was 46.8 months. The 5-year recurrence-free survival rate was 89.7% in the SLNB group and 88.7% in the ALND group. The authors conclude that the omission of ALND was noninferior to the more extensive surgery in patients with clinically node-negative breast cancer who had SLN macrometastases, most of whom received nodal radiation therapy (quick take video summary).