Oncological Outcomes of Omitting Axillary Surgery in Early Breast Cancer: A Systematic Review and Meta‐Analysis

ABSTRACT Background and Objectives Increasing evidence supports the oncologic safety of omitting axillary surgery for patients with early breast cancer undergoing breast conserving surgery (BCS). However, there is concern that sentinel lymph node biopsy (SLNB) is necessary to inform adjuvant radiotherapy and systemic therapy decisions. The aim was to assess the oncological and survival outcomes of omitting surgical axillary staging in early breast cancer. Methods A systematic literature search of relevant databases was performed. Eligible studies compared omission of axillary surgery with conventional axillary staging. A meta‐analysis using the Mantel‐Haenszel method was performed to calculate pooled risk ratios (RR) for axillary recurrence (AR), disease‐free survival (DFS) and overall survival (OS) for omission of axillary surgery compared with conventional axillary surgery. Results Five studies involving 8108 patients were included. Omission of axillary surgery was associated with a higher risk of AR (RR 3.82 95% CI 1.48–9.82, p < 0.005). No significant differences were observed in in DFS (RR 1.09 95% CI 0.91–1.30, p = 0.33) or OS (RR 1.06 95% CI 0.72–1.55; p = 0.78). Conclusions Axillary surgery may be safely omitted in a highly select group of older patients with favourable tumour biology undergoing BCS. Multidisciplinary team input remains essential to appropriately select adjuvant treatments when nodal staging is omitted.