Sentinel Lymph Node Biopsy After Preoperative Chemotherapy for Breast Cancer: Findings from the Austrian Sentinel Node Study Group

Background  Sentinel lymph node biopsy (SLNB) has become an accurate alternative to axillary lymph node dissection for early breast cancer. However, data are still insufficient as regards the combination of SLNB with preoperative chemotherapy (PC). Methods  The Austrian Sentinel Node Study Group investigated 167 patients who underwent SLNB and axillary lymph node dissection after 3 to 6 courses of PC. SLNB was limited to patients with a clinically negative axilla after PC. Blue dye was used in 29 cases (17%), and tracers were used in 20 (12%). A combination of the two methods was applied in most patients (n = 120; 72%). Results  At least 1 sentinel lymph node (SLN) was identified in 144 patients (identification rate, 85%): in 86% by blue dye alone, in 65% by tracers alone, and in 88% by a combination of methods. The SLN was positive in 70 women (42%) and was the only positive node with otherwise negative axillary nodes in 39 patients (23%). In 6 cases, the SLN was diagnosed as negative although tumor infiltration was detected in an upper node of the axillary basin (false-negative rate, 8%; 6 of 76 patients; sensitivity, 92%). At least 62 patients (37%) were free of tumor cells in the SLN and in the axillary nodes. Conclusion  The results of SLNB after PC are comparable to the results of SLNB without PC. Further investigation in a prospective setting is warranted to confirm these promising results.