The clinical implication of the number of lymph nodes harvested during sentinel lymph node biopsy and its effects on survival outcome in patients with node-negative breast cancer

BACKGROUND: The optimal number of sentinel lymph nodes (SLN) that need to be harvested to achieve favorable survival outcome during a SLN biopsy (SLNB) has not yet been established. METHODS: Six hundred and thirteen patients with clinically node-negative breast cancer who underwent SLNB were reviewed. Survival outcomes according to the number of total harvested lymph nodes (THLNs), defined as the sum of enumerated SLNs and non-SLNs were analyzed. RESULTS: Patients with only 1 THLN showed lower recurrence-free survival (RFS) as compared to those with ≥2 THLNs (p = 0.049). In multivariate analysis, only 1 THLN was associated with poor RFS (HR = 2.711; p = 0.029). CONCLUSIONS: Removing at least 2 lymph nodes during SLNB may be acceptable. Harvesting only 1 lymph node should be undertaken cautiously because of false negative results and increasing the subsequent recurrence rate.restrictio