Axillary lymph node dissection vs. sentinel node biopsy for early-stage clinically node-negative breast cancer: a systematic review and meta-analysis.

ΟBJECTIVE: This study aimed at comparing survival outcomes between systematic axillary lymph node dissection (ALND) vs sentinel lymph node and axillary lymph node dissection only if sentinel positive (SLN ± ALND) in early-stage, clinically node-negative breast cancer patients. ΜETHODS: A systematic review and meta-analysis adhered to PRISMA guidelines was performed. Included studies were prospective randomized controlled trials (RCTs) comparing survival outcomes of ALND vs. SLN ± ALND in early-stage, node-negative breast cancer patients. Patients enrolled were only those with tumor size lower than 4 cm, clinically negative nodes and treated with breast-conservative surgery. Primary endpoints were locoregional recurrence, overall death and cancer-related death. RESULTS: There were four studies included in the analysis, enrolling overall 2982 patients, of which 1494 in ALND arm and 1488 in the SLN ± ALND arm. No statistically significant difference was observed in locoregional recurrence, breast cancer-related death and overall death. Locoregional recurrence was observed in 2.8% (ALND) vs. 4.1% (SLND ± ALND), (RR 0.69, 95% CI 0.20-2.30). Overall death rate was 7.0% vs. 6.8% respectively, (RR 1.00, 95% CI 0.73-1.39, I 2  = 28.7%). Breast cancer-related death was 3.6% vs. 3.5%, respectively (SLN ± ALND), (RR 1.11, 95% CI 0.70-1.78, I 2  = 0%). No statistically significant difference was observed in any of secondary study outcomes. CONCLUSIONS: Systematic axillary axillary lymph node dissection provides no survival benefit compared with sentinel lymph node dissection for early-stage clinically node-negative breast cancer patients.