Long-term Outcomes of Early Breast Cancer Stratified by Axillary Ultrasound Assessment

De-escalation of axillary lymph node (ALN) surgery in early breast cancer is increasingly common. This study aimed to identify patients suitable for this approach by comparing long-term survival based on preoperative axillary ultrasound (AUS).

Patients undergoing surgery at Yonsei University Severance Hospital between January 2010 and December 2017 were categorized into "no suspicion" and "low suspicion" groups based on AUS findings.

Median follow-up duration was 92 months. The 10-year recurrence-free survival (RFS) and overall survival rates for the no suspicion and low suspicion groups were 94.2% and 90.1% (p < 0.001) and 93.1% and 93.0% (p = 0.177), respectively. The 10-year locoregional RFS rates were 96.8% and 96.1% (p = 0.060). Among node-positive patients, 19.9% in the no suspicion group had three or more metastatic ALNs compared with 23.0% in the low suspicion group (p = 0.012). Recurrence was associated with T stage, N stage, histologic grade, Ki-67, and subtype, whereas mortality was linked to age, T stage, N stage, histologic grade, and subtype.

The low suspicion and fine-needle aspiration biopsy-negative group had poorer prognostic biomarkers, leading to differences in recurrence but not in overall survival. The preoperative ALN status did not affect survival rates. Even in patients with cT2 and low suspicion of ALN, the rate of three or more metastatic ALNs was low, suggesting that further axillary surgery may not be necessary if two or fewer metastatic lymph nodes are found in the sentinel lymph node.