Abstract PS2-03-20: Feasibility of the omission of axillary surgery in node-negative early breast cancer: a systematic review and meta-analysis

Abstract Introduction: Recent and historical trials have suggested that the omission of axillary surgery is oncologically safe in node-negative early breast cancer. This meta-analysis investigates the feasibility of the omission of axillary surgery (SLNB or ALND) in terms of oncological outcomes and adjuvant treatment decisions. Method: A systematic search of Medline, Embase and Cochrane Central was conducted. Random-effect meta-analysis was conducted to compare recurrence and survival outcomes between omission of axillary surgery and SLNB or ALND. Differences in real-world adjuvant treatment decisions and patient reported outcomes were investigated. Results: Ten studies (omission, n=3716; SLNB/ALND, n=4604/785) investigated oncological outcomes (pooled rates, T1 - 88%; Grade 1-2, 80%; ER-positive 91.2%; HER2-positive 4.4%; ductal carcinoma 74%). In the omitted group, the pooled rates of local, axillary and distant recurrence (follow-up, 8 years 9 months) were 3.6% (95%CI,2.0-6.5%), 2.5% (95%CI,1.3-4.8%; 5year, 1.0%) and 3.6% (95%CI,2.0-6.5%; 5year, 2.7%), respectively. In comparison to SLNB/ALND, there were no differences in local recurrence (OR 0.91; 95%CI,0.56-1.50), distant metastasis (OR 0.91; 95%CI,0.56-1.50), BCM (OR 1.00; 95%,CI 0.63-1.60), OS (HR 0.88; 95%CI,0.65-1.19) or DFS (HR 0.91; 95%CI,0.76-1.11). Axillary recurrence was higher in the omission group compared to SLNB/ALND (OR 4.42, 95%CI,1.5-12.8) but not in SLNB alone (OR 2.85 95%CI 0.1-133.8). Omission of axillary surgery was associated with lower rates of adjuvant chemotherapy, radiotherapy and hormonal treatment but quality of evidence was poor. Conclusion: Omission of axillary surgery is safe in node-negative early breast cancer. Prospective data is required to investigate the impact of omission on adjuvant treatment decision. Citation Format: J. Lucocq, H. Baig, K. Elder, G. Urquhart, R. Sharma, L. Romics, B. Elsberger. Feasibility of the omission of axillary surgery in node-negative early breast cancer: a systematic review and meta-analysis [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS2-03-20.