Intentional Segmentectomy for Clinical T1 N0 Non-small Cell Lung Cancer: Survival Differs by Segment

Abstract

Outcomes after segmentectomy compare favorably with those after lobectomy in patients with stage I non-small cell lung cancer (NSCLC). Whether long-term outcomes vary by segmentectomy location is unclear. We investigated whether disease-free survival (DFS) and overall survival (OS) differ by segmentectomy location after intentional segmentectomy for clinical T1 N0 M0 NSCLC. Patients who received intentional segmentectomy for cT1 N0 M0 NSCLC from 2000 to 2018 were reviewed. Patients with prior lung cancer, forced expiratory volume in 1 second of less than 50%, or R1/R2 resection were excluded. Segmentectomy groups were left (L) basilar, L segment 6, L lingula, L trisegment; right (R): basilar (R_Bas), segment 6 (R_S6), and R upper. The 5- and 10-year DFS and OS were estimated using Kaplan-Meier and compared between groups using the log-rank test. Factors associated with DFS and OS were determined using Cox proportional hazards models. In total, 416 patients met the inclusion criteria. Segmentectomy groups differed with regard to surgical approach, mediastinal lymphadenectomy, lymphovascular invasion, tumor histology, margin distance, and adjuvant therapy. Long-term outcomes were worst after R_S6 resection (5-year DFS, 57.6% [95% confidence interval {CI}, 45.7%-72.7%]; OS, 66.3% [95% CI, 54.7%-80.3%]) and best after R_Bas resection (5-year DFS, 77.1% [95% CI, 59.2%-100%]; OS, 79.5% [95% CI, 60.9%-100%]). On multivariable analysis, R_S6 resection was independently associated with DFS vs R_Bas (hazard ratio, 2.89; 95% CI, 1.18-7.08; P= .02) and OS vs R_Bas (hazard ratio, 4.35; 95% CI, 1.61-11.76; P= .004). Resection of R_S6 is independently associated with worse DFS and OS in patients receiving intentional segmentectomy for cT1 N0 M0 NSCLC and may warrant more extensive resection, complete lymph node dissection, and closer postoperative surveillance.