Examined lymph node counts ≤6 are correlated with an unfavorable prognosis in stage IA NSCLC patients following sublobar resection: a retrospective study employing propensity score matching analysis.

Complete lymph node dissection improves staging accuracy in non-small cell lung cancer (NSCLC) patients and may improve outcomes in select patients. However, the benefit of increased lymph node examination in patients with stage IA NSCLC remains unclear. Therefore, this study aimed to explore the relationship between the examined lymph node (ELN) counts and the prognosis of patients with stage IA NSCLC following sublobar resection. We obtained data from the Surveillance, Epidemiology, and End Results (SEER) 17 registry study database (2010-2019), including patients with stage IA NSCLC who underwent sublobar resection. Patients with missing ELN counts were excluded. Cox regression analysis showed a correlation between ELN count and cancer-specific survival (CSS). Propensity score matching (PSM) compared survival between ELN ≤6 and ELN >6 groups. Analysis used Empower Stats and R software. In this study, 5,851 patients with NSCLC and pathological stage IA disease were included. Patients with more than 6 ELNs were older, more likely to be Caucasian, and more likely to have lung adenocarcinoma. After PSM, baseline characteristics were balanced between ELN groups. Univariate analysis showed better survival in the ELN >6 group, with a hazard ratio (HR) of 0.75 [95% confidence interval (CI): 0.64-0.88, P=0.0004], which was consistent in multivariate analysis (HR: 0.76, 95% CI: 0.64-0.89, P=0.0008). Kaplan-Meier survival curves indicated significantly better survival in the ELN >6 group, consistent across wedge and segmental resection subgroups. In conclusion, our findings indicate that an ELN count of ≤6 following sublobar resection in patients with stage IA NSCLC is linked to an unfavorable prognosis. We recommend dissecting more than 6 nodes during sublobar resections in stage 1A NSCLC patients.