Abstract
The optimal treatment strategy for pathologic single-station N2 (pN2a1) non-small cell lung cancer (NSCLC)-surgery first followed by adjuvant treatment (SF) or neoadjuvant therapy followed by surgery (NS)-remains unclear. We compared disease-free survival (DFS) and overall survival (OS) after NS versus SF for pN2a1 NSCLC. We retrospectively identified patients with pN2a1 NSCLC resected between 2000 and 2018. Patients in the SF group had cN0 disease and were treated with surgery before adjuvant chemotherapy; patients in the NS group had known preoperative nodal disease, cN2 disease, and were treated with neoadjuvant therapy before surgery. The matching-weights procedure was applied to generate a cohort with similar characteristics between groups. DFS and OS were calculated using the Kaplan-Meier approach and compared between groups using weighted log-rank test and Cox proportional hazards models. We identified 227 patients with pN2a1 disease: 121 treated with SF and 106 with NS. After the matching-weights procedure, 5- and 10-year DFS were 45% and 27% for SF versus 26% and 21% for NS (log-rank P = 0.056; hazard ratio [HR], 1.61; 95% confidence interval [CI], 0.98-2.65); 5- and 10-year OS were 49% and 30% for SF versus 43% and 20% for NS (log-rank P = 0.428; HR, 1.24; 95% CI, 0.67-2.28). SF and NS for pN2a1 NSCLC resulted in similar survival. A study comparing SF for known preresectional pN2a1 with occult pN2a1 disease could be a next step. Further investigation of SF for known N2a1 versus occult pN2a1 disease could power a clinical trial focused on N2a NSCLC.