Optimization of regional nodal irradiation in the era of sentinel lymph node biopsy.

Historically, axillary lymph node dissection (ALND) was the standard management for axillary sentinel lymph node (SLN)-positive patients, because it enables full assessment of overall axillary lymph node (ALN) metastasis status and favorable local-regional control1,2. Strikingly, no differences in axillary regional recurrence or overall survival (OS) have been observed with versus without ALND among patients with early breast cancer with limited SLN involvement in several randomized, controlled trials, including the ACSOG Z0011 and AMAROS trial3,4. In the era of sentinel lymph node biopsy (SLNB), SLNB has replaced ALND as the standard approach for patients with 1 or 2 positive SLNs5. These changes in clin-ical practice should be considered for the optimization of regional nodal irradiation (RNI) fields.