In 2015, the US Food and Drug Administration approved nivolumab as the first immunotherapy for patients with advanced non-small cell lung cancer (NSCLC). However, population-based survival benefit studies after the introduction of immunotherapy in lung cancer are lacking. This study examined overall survival (OS) and cancer-specific survival in patients with NSCLC in the pre immunotherapy and immunotherapy eras.

This study used the Surveillance, Epidemiology, and End Results database, which spanned 17 registries from 2000 to 2020. Two cohorts were delineated: preimmunotherapy (2010-2014) and immunotherapy (2015-2020), which coincided with nivolumab's approval.

This study included 191,802 patients, 90,807 in the preimmunotherapy era and 100,995 in the immunotherapy era. OS was significantly higher in the immunotherapy era, as shown by Kaplan-Meier curves (1-year OS, 40.1% vs. 33.5%; 3-year OS, 17.8% vs. 11.7%; 5-year OS, 10.7% vs. 6.8%; median OS, 8 vs. 7 months; p < .001 by log-rank test). Similarly, cancer-specific survival improved in the immunotherapy era (1-year survival, 44.0% vs. 36.8%; 3-year survival, 21.7% vs. 14.4%; 5-year survival, 14.3% vs. 9.0%; median OS, 10 vs. 8 months; p < .001 by log-rank test). Survival rates were significantly better in the immunotherapy era, as confirmed by multivariate analysis with a Cox proportional hazards model after adjusting for age, sex, race, income, and geographical area (adjusted hazard ratio, 0.830; 95% CI, 0.821-0.840; p < .001).

In summary, the survival rate of patients with metastatic NSCLC has improved since the introduction of immunotherapy.