Clinical Significance of Station 3A Lymph Node Dissection in Patients with Right-Side Non-Small-Cell Lung Cancer: A Retrospective Propensity-Matched Analysis.

Abstract

To investigate the prognostic impact of station 3A lymph node (LN) dissection in patients with right-side non-small-cell lung cancer (NSCLC). We retrospectively reviewed data of 1906 patients with primary right-side NSCLC who underwent lobectomy between January 2005 and December 2017 (570 patients underwent station 3A LN dissection and 1336 patients did not). Propensity score matching was conducted to minimize the effects of potential confounding factors. Disease-free survival (DFS) and overall survival (OS) were analyzed. The metastasis rate of station 3A LN was 15.3% (87/570), which was second only to station 4 (17.3%). Only stations 10 and 11 LN metastases were found to be independent risk factors for station 3A LN metastasis (odds ratio = 19.43, 95% CI 1.21-311.12; P = 0.036 and odds ratio = 53.28, 95% CI 2.02-1404.90; P = 0.016, respectively). After propensity score matching, patients with dissection of station 3A LNs showed higher DFS (5-year DFS, 52.4% vs. 37.1%; P = 0.001) and OS (5-year OS, 58.8% vs. 48.7%; P = 0.007) than those without dissection. Subgroup analysis indicated that station 3A LN dissection was associated with significantly higher DFS and OS in patients with stage II and III disease. In multivariate survival analysis, dissection of 3A LNs retained its independent favorable effect on both DFS (hazard ratio = 0.76, 95% CI 0.64-0.90; P = 0.001) and OS (hazard ratio = 0.73, 95% CI 0.60-0.88; P = 0.001). Station 3A LN involvement was not rare and station 3A LN dissection was associated with a more favorable prognosis in patients with right-side NSCLC.