Comparison of prognostic impact of lymphovascular invasion in stage IA non-small cell lung cancer after lobectomy versus sublobar resection: A propensity score-matched analysis

Objectives: Lymphovascular invasion (LVI) is a well-known poor prognostic factor after lobectomy for non-small cell lung cancer. However, the prognostic effect of LVI in patients who undergo sublobar resection has not been fully evaluated. Thus, we compared the prognostic impact of LVI in stage IA patients who underwent lobectomy or sublobar resection. Materials and Methods: We retrospectively reviewed the data from patients with stage IA NSCLC who underwent surgical resection between 2007 and 2016. The prognostic impact of LVI was calculated by the Cox proportional hazard regression model. To adjust for the differences in confounding variables between LVI-positive and LVI-negative patients, propensity score matching (PSM) was carried out in patients who underwent lobectomy or sublobar resection. Results: Among the stage IA NSCLC patients (n = 2134), 184 (8.6%) had been diagnosed with LVI, of whom 144 (8.9%) were in the lobectomy group (n = 1614) and 40 (7.7%) were in the sublobar resection group (n = 520). In multivariable analysis, LVI was a significant risk factor for both overall survival (OS) (hazard ratio [HR], 2.03; 95% confidence interval [CI], 1.39-2.96; p < 0.001) and recurrence-free survival (RFS) (HR, 2.31; 95% CI, 1.68-3.17; p < 0.001). After PSM, the prognostic impact of LVI was greater in the sublobar resection group (HR = 4.93 and 4.25 for OS and RFS, respectively) than in the lobectomy group (HR = 1.77 and 2.51 for OS and RFS, respectively). Conclusions: The presence of LVI was significantly associated with worse OS and RFS in stage IA NSCLC patients. The prognostic impact of LVI was more pronounced in the sublobar resection group than in the lobectomy group.