117P Tumour spread through air spaces is a determiner for treatment of clinical stage I non-small cell lung cancer: Thoracoscopic segmentectomy vs lobectomy

The aim of this study was to analyse the prognostic influence of tumour spread through air spaces (STAS) on thoracoscopic segmentectomy compared with lobectomy for clinical stage I non-small cell lung cancer (NSCLC). Patients who underwent thoracoscopic segmentectomy or lobectomy for clinical stage I NSCLC from September 2020 through September 2023 at a high-volume thoracic unit. were included. Recurrence-free survival (RFS) and overall survival (OS) between the two procedures were assessed using Kaplan-Meier analysis with log-rank test. Cox regression model was used to analyse independent factors for survivals. STAS was available in 785 patients, including 151 (19.2%) patients with STAS and 634 (80.8%) patients without STAS. The STAS positive group had significantly higher vascular and lymphatic invasion. The median follow-up was 25.1 months (IQR 20.1-31.1). In the group without STAS, there were no survival difference between segmentectomy (n = 87) and lobectomy (n = 547) (3-year RFS: 77.4% vs 82.6%, p = .350; 3-year OS: 87.5% vs 95.3%, p = .190). Whereas worse survival was found in segmentectomy for patients with STAS (n = 16) compared to lobectomy (n = 135) (3-year RFS: 69.8% vs 82.7%, p < .001; 3-year OS: 58.4% vs 89.0%, p < .001). In multivariable analysis, segmentectomy was an independent prognostic factor for RFS in patients with STAS (HR 9.28, 95% CI 7.66 to 18.18), as well as pleural invasion (HR 5.25, 95% CI 1.44 to 19.16). Moreover, segmentectomy (HR 13.55, 95% CI 3.98 to 46.20) and older age (per 5-year increase: HR 1.96, 95% CI 1.11 to 3.48) were independent prognostic factors of OS among patients with STAS. In this study there was a superior RFS and OS for lobectomy vs. segmentectomy for clinical stage I NSCLC with STAS.