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 (ΔNLR) <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 ΔNLR <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: ΔNLR <1 was a significant long‐term survival factor compared to ΔNLR ≥1 in advanced NSCLC patients treated with nivolumab.