Retrospective analysis of long-term survival factors in patients with advanced non-small cell lung cancer treated with nivolumab

Background Nivolumab, an immune checkpoint inhibitor (ICI), has changed the treatment paradigm for advanced non-small cell lung cancer (NSCLC). However, factors associated with long-term survival in NSCLC patients treated with ICIs remain unknown. This study aimed to evaluate patient characteristics and clinical laboratory changes related to long-term survival in NSCLC patients treated with nivolumab, using real-world data. Methods We retrospectively reviewed the medical records of consecutive patients with advanced NSCLC with Eastern Cooperative Oncology Group performance status (ECOG-PS) <= 1 treated with nivolumab. We defined patients with overall survival (OS) >= 3 years as long-term survivors. We evaluated the differences in patient characteristics and tumor response between nonlong-term survivors and long-term survivors and performed univariate and multivariate analyses of factors associated with long-term survival. Results Out of 213 patients with advanced NSCLC treated with nivolumab, 162 patients with ECOG-PS <= 1 were included in the study. Young age, ECOG-PS 0, absolute neutrophil count decrease, lymphocyte percentage increase, and neutrophil-to-lymphocyte ratio (NLR) change (Delta NLR) <1 were significantly associated with long-term survival. Long-term survivors had significantly higher response and disease control rates than nonlong-term survivors. Multivariate analysis showed that Delta NLR <1 was significantly associated with long-term survival. Further, OS was significantly different between the PS 0 and PS 1 groups (median OS: 32.0 months vs. 10.6 months) and the nonincreasing NLR and increasing NLR groups (median OS: 20.8 months vs. 5.7 months). Conclusions Delta NLR <1 was a significant long-term survival factor compared to Delta NLR >= 1 in advanced NSCLC patients treated with nivolumab.