Late Axillary Recurrence After Negative Sentinel Lymph Node Biopsy is Uncommon

This study was designed to determine the incidence of late axillary recurrence (AR) in patients with negative sentinel lymph node biopsy (SLNB) and provide a comparison with SLNB positive patients who underwent axillary lymph node dissection (ALND). Retrospective analysis of prospectively collected data on all breast cancer patients with negative SLNB from January 1997 to December 2000 was performed on a large, institutional database. Primary outcome was cumulative incidence of AR as a first event with/without concurrent local recurrence. SLNB positive patients who went on to ALND during the same timeframe were comparatively analyzed. A total of 1529 eligible patients were identified (median age 58 years, median tumor size 1.0 cm): 1297 (85 %) underwent lumpectomy; 1099 (75 %) received adjuvant radiation; and 874 (80 %) were estrogen receptor-positive. At 10.8 (range 0-16) years median follow-up, overall incidence of AR as a first event was low (n = 13). Cumulative incidence was 0.6 % [95 % confidence interval (CI) 0.2-0.9] 5 years after SLNB, and 0.9 % (95 % CI 0.4-1.4, 95 % CI 0.5-1.6) at 10 and 15 years. Late AR (> 5 years after surgery) occurred in five patients. Median overall survival after AR was 4.6 years; median distant disease-free survival after AR was 3.8 years. Late AR was also low in a contemporaneous group of SLNB positive patients undergoing ALND. In this group, cumulative incidence of AR was 0.7 % (95 % CI 0.1-1.3) 5 years after surgery, and 0.8 % (95 % CI 0.2-1.5) at 10 and 15 years. Late AR after negative SLNB is rare; the majority of ARs are in the first 5 years after surgery. Prognosis after these events is poor. SLNB remains a safe and effective procedure for axillary evaluation in breast cancer.