Sentinel lymph node BIOPSY after neoadjuvant therapy in breast cancer patients with lymph node involvement at diagnosis. Could wire localization of clipped node improve our results

Abstract Introduction Sentinel lymph node biopsy (SLNB) after neoadjuvant therapy (NAT) in node-positive (N+) breast cancer patients at diagnosis remains a controversial issue, with no consensus on implementation or safety. Objectives We sought to assess the accuracy of SLNB after NAT in biopsy-proven N+ cases at diagnosis and the efficacy and accuracy of wire localization of the clipped node to improve results. Material and methods A cross-sectional diagnostic technique validation study in N+ patients following NAT was performed. The biopsy-proven affected lymph node was clipped at diagnosis. SLNB and axillary lymph node dissection (ALND) were performed in cases of clinical-radiological lymph node response after NAT. For the purposes of our study we added wire localization of the clipped node. Results 103 patients were included (mean age, 54.4 years [± 12.7]). Wire marking was performed in 28 cases. The overall identification rate (IR) of SLN was 81.6%. The median number of nodes removed was 2 (range 2). The overall false negative rate (FNR) was 6.1%. Sensitivity and overall accuracy were 93.9% and 95.2%, respectively (area under curve 0.97). In the double-marked (clip and wire) group the FNR decreased to 0% and accuracy was 100%. Axillary pathologic complete response was observed in 24.3% of cases. Conclusions SLNB is useful in node-positive patients at diagnosis who respond to NAT. Combining this with preoperative wire localization of the biopsied lymph node reduces the FNR without increasing the number of complications.