Breast Cancer by AJCC V8 Anatomic Stage

Recent studies have demonstrated the safety of de-escalation of nodal surgery for clinically node-positive breast cancer patients after a favorable response to neoadjuvant systemic therapy (NST). These studies excluded patients with clinically node-positive stage 2 or 3 (cN2, cN3) disease. Consequently, the current guidelines recommend axillary lymph node dissection (ALND) for patients with cN2/cN3 breast cancer, even after a favorable response to NST. Many cN2/cN3 patients achieve nodal pathologic complete response (pCR) after NST, and this has raised interest in less invasive surgical approaches for the management of the axilla in this setting. We aim to evaluate the pathologic concordance between lymph node status post neoadjuvant therapy (ypN) derived from targeted axillary dissection (TAD) and ALND performed sequentially under the same anesthesia in patients with cN2/cN3 who convert to clinically node-negative (ycN0) following completion of NST. If a high level of concordance is determined between the ypN status determined from the TAD and the ALND, our next step would be to expand the trial to include a larger number of patients, making it multi-institutional, in order to power the study for more meaningful analysis.