10-Year Outcomes of Targeted Axillary Surgery after Neoadjuvant Chemotherapy in Breast Cancer

Background: When pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) is achieved, identifying traces of the previous tumor site or lymph nodes and performing accurate surgery becomes challenging. We conducted ultrasound-guided targeted axillary surgery (TAS) in patients with node-positive breast cancer treated with NAC. Survival outcomes were compared with those of patients who underwent conventional axillary lymph node dissection (ALND). Methods: We conducted a retrospective analysis of 235 patients (TAS, n=78; ALND, n=157) with cT1-3N1-2 breast cancer who underwent NAC followed by surgery from 2012 to 2017. Patients were treated with standard treatments, and oncologic results, including locoregional recurrence-free survival, distant metastasis-free survival, and overall survival (OS), were assessed over a 10-year follow-up period. Results: There was no significant difference in oncologic outcomes between two groups and based on subtypes, including hormone receptor (HR)-positive, HER2-positive, and triple-negative breast cancer (TNBC). In the HR-positive breast cancer group, the TAS and ALND groups showed very similar trends . In HER2-positive breast cancer, although not statistically significant, the survival outcomes were better in the TAS group than in the ALND group. However, the OS in the TAS group for TNBC was lower than that in the ALND group, though not significantly. Conclusions and Relevance: This study demonstrates that TAS is comparable to ALND in terms of 10-year oncological outcomes across different types of node-positive breast cancer, suggesting its potential as a viable alternative.