Sentinel Lymph Node Surgery After Neoadjuvant Chemotherapy is Accurate and Reduces the Need for Axillary Dissection in Breast Cancer Patients

Objective: Sentinel lymph node (SLN) surgery is widely used for nodal staging in early-stage breast cancer This study was pet-formed to evaluate the accuracy of SLN surgery for patients undergoing neoadjuvant chemotherapy versus patients undergoing surgery first. Summary Background Data: Controversy exists regarding the timing of SLN surgery in patients planned for neoadjuvant chemotherapy Proponents of SLN surgery after chemotherapy prefer a single surgical procedure with potential for fewer axillary dissections Opponents are early studies with low identification rates and high false-negative rates after chemotherapy. Methods: A total of 3746 patients with clinically node negative T1 -T3 breast cancer underwent SLN surgery front 1994 to 2001. Clinicopathologic data were reviewed and comparisons made between patients receiving neoadjuvant chemotherapy and those undergoing surgery first Results: Of the patients, 575 (15.3%) underwent SLN surgery after chemotherapy and 3171 (84.7%) underwent surgery first. Neoadjuvant patients were younger (51 vs. 57 years, P < 0.0001) and had more clinical T2-T3 tumors (87.3% vs 18.8%, P < 0.0001) at diagnosts SLN identification rates were 97.4% in the neoadjuvant group and 98.71% in the surgery first group (P = 0.017) False-negative rates were similar between groups (5/84 [5.9%] in neoadjuvant vs 22/542 [4.1%] in the surgery first group, P = 0.39) Analyzed by presenting T stage, there were fewer positive SLNs in the neoadjuvant group (T1: 12.7% vs 19.0%, P = 0 2; T2: 20.5% vs. 36.5%. P < 0.0001. T3. 30.4% vs. 51.4%, P = 0.04). Adjusting for clinical stage revealed no differences in local-regional recurrences, disease-free or overall survival between groups Conclusions: SLN surgery after chemotherapy is as accurate for axillary staging as SLN surgery prior to chemotherapy. SIN surgery after chemotherapy results in fewer positive SLNs and decreases unnecessary axillary dissections