Sentinel-lymph-node-based management or routine axillary clearance? Three-year outcomes of the RACS Sentinel Node Biopsy versus Axillary Clearance (SNAC) 1 trial

Abstract

Purpose We sought to determine whether the benefits of sentinel-node-based management (SNBM) over routine axillary clearance (RAC) at 1 year persisted to 3 years of follow-up. Methods 1088 women with clinically node negative breast cancer were randomly assigned to SNBM versus RAC. Upper limb volume, symptoms and function were assessed at 1, 6, 12, 24 and 36 months after surgery objectively with upper limb measurements by clinicians, and subjectively by patients’ using validated self-rating scales. Results Upper limb volume increased in both groups over the first 2 years and differed between the two groups all time points beyond 1 month (P<0.02), but then plateaued. Upper limb swelling was no worse in women who had axillary clearance as two-stage procedure than in women assigned RAC as a one-stage procedure. Upper limb volume had increased 15% or more in 6.0% at 6 months and 17.6% at 3 years in those assigned RAC versus 4.2% and 11.9% in those assigned SNBM. Reductions in upper limb movement were also greater with RAC than SNBM over 6 months, but improved and were similar in the two groups from 1 to 3 years. Subjective ratings of upper limb swelling, symptoms, dysfunction, and disability over 3 years were worse in the RAC group. Upper limb swelling at 3 years was rated severe by few women (1.1%), but moderate by 9.4% in the RAC group and 2.5% in the SNBM group (P<0.001). Conclusions The benefits of SNBM over RAC persist 3 years after surgery.