Inclusion of Surgery in Multimodality Treatment is Predictive of Better Survival in Stage IIIA Non-small Cell Lung Cancer: An Inverse Probability Treatment-Weighting Analysis

Introduction: Stage IIIA non-small cell lung cancers (NSCLC) are treated with surgery-based multimodality approach or definitive chemoradiation therapy plus durvalumab consolidation. It is not clear whether surgery-based multimodality therapy has any survival advantage over definitive chemoradiation plus immunotherapy consolidation. Method: National Cancer Database (NCDB) was used to identify NSCLC patients at stage IIIA (AJCC8, T3N1/T4N0-1 or T1N2/T2N2) who are treated with surgery-based multimodality approach or definitive chemoradiation plus durvalumab. Survival between groups were compared using inverse probability treatment weighting (IPTW)-adjusted Kaplan Meier curves and Cox proportional hazards regression analysis. Results were independently confirmed by Landmark Inverse and Clone Censor Weight analyses to address immortal time bias. Results: From 2017 to 2019, 24,170 patients are identified as potentially resectable stage IIIA (T3N1, T4N0-1, T1N2/T2N2). Among them, 2,615 (10.8%) received surgery-based multimodality therapy and 2,985 (12.4%) received definitive chemoradiation plus durvalumab. Surgery based multimodality approach had significant survival advantage over definitive chemoradiation plus durvalumab (HR 0.74; 95% CI 0.69-0.79, P < .001). The median overall survival (mOS) for the definitive chemoradiation plus durvalumab group was 48.59 m whereas mOS was not reached for surgery-based multimodality group. This trend persisted in both N2 negative and positive tumors. Neoadjuvant chemotherapy was just as effective as adjuvant chemotherapy and delay of immunotherapy consolidation to 12 weeks after initiation of chemoradiation did not negatively affect survival outcome. Conclusion: For stage IIIA NSCLC patients, surgery-based multimodality treatment outperformed chemoradiation plus durvalumab in survival.