From cN+ to ycN0: Sentinel Node Biopsy as a Safe Alternative to ALND Post-Neo-Adjuvant Chemotherapy

Sentinel lymph node biopsy (SLNB) has largely replaced axillary lymph node dissection (ALND) for breast cancer (BC) patients receiving neo-adjuvant chemotherapy (NAC). It is routinely used in individuals who present with clinically node-negative (cN0) disease, but its value in those who begin as clinically node-positive (cN+) remains unsettled. We retrospectively reviewed BC cases treated with NAC followed by SLNB to determine the relevance of this approach. Clinical features and oncologic outcomes were contrasted between patients who were cN0 or cN+ before NAC, as well as according to the type of axillary surgery performed. The study involved 291 patients: 131 were cN0 and 160 were cN+ converting to ycN0 after NAC. After a median monitor period of 43 months, axillary relapse was identified in three cN0 (2.3%) and two cN+ (1.3%) patients. No significant discrepancies were found in disease-free survival, distant disease-free survival, overall survival, or breast-cancer-specific survival between the groups or between SLNB-only and ALND procedures. When performed after NAC, SLNB appears to be a reliable option with favorable prognostic patterns and low axillary recurrence rates for both cN0 and cN+ patients.