Clinical Significance of Regional Lymph Node Evaluation During Sublobar Resection in Lung Cancer

This study evaluated the prognostic effect of regional lymph node evaluation (LNE) in patients with non-small cell lung cancer (NSCLC) who underwent sublobar resection based on harvested node stations.We retrospectively reviewed the data of patients with NSCLC who underwent sublobar resection at Asan Medical Center between 2007 and 2016. To adjust for the differences in confounding variables between the groups, propensity score-based inverse probability of treatment weighting (IPTW) was performed.In the LNE group with pathological N0 disease (n = 522), 458 (87.7%) patients underwent both N1 and N2 LNE (N1 + N2 group) and 64 (12.3%) underwent only N2 LNE (N2 alone group). The N1 + N2 group had better prognosis before (P < .001) and after (P = .019) IPTW adjustment. Similar results were obtained even in patients with tumor size less than or equal to 2 cm (P = .032) or who underwent wedge resection (P = .041). According to IPTW-adjusted multivariable analysis, the performance of regional LNE was a significant prognostic factor for survival outcome (hazard ratio, 0.45; 95% confidence interval, 0.27-0.74; P = .002).LNE is a critical process during sublobar resection in patients with NSCLC. Regional LNE during sublobar resection can significantly affect clinical outcomes even in patients with wedge resection or with tumor size less than 2 cm.