Gustave Roussy Immune Score Is a Prognostic Factor for Chemotherapy-Naive Pulmonary Adenocarcinoma With Wild-Type Epidermal Growth Factor Receptor

BACKGROUND: The Gustave Roussy Immune Score (GRIm-Score) was developed based on the Royal Marsden Hospital (RMH) prognostic score for the purpose of a better patient selection for immunotherapy phase I trials. This scoring system is simply calculated by neutrophil-to-lymphocyte ratio, lactate dehydrogenase (LDH), and serum albumin concentration. The aim of our study was to determine whether GRIm-Score is a practically useful prognostic biomarker for advanced non-small cell lung cancer (NSCLC) patients treated with cytotoxic chemotherapy or epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI). METHODS: This retrospective and single institutional study collected 185 adenocarcinomas without active EGFR mutation, 115 squamous cell carcinomas treated with first-line cytotoxic chemotherapy, and 140 NSCLCs with mutant EGFR treated with first- or second-generation EGFR-TKI monotherapy. These treatments were initiated between July 2007 and March 2018 at our hospital. We compared overall survival (OS) and progression-free survival (PFS) between high and low GRIm-Score groups. Using multivariate Cox proportional hazard analyses, we also found prognostic factors of survival times. RESULTS: The OS and PFS of low GRIm-Score group were significantly longer than those of high-score group in wild-type EGFR adenocarcinoma (low vs. high; median OS, 18.4 vs. 5.1 months, P < 0.01, and median PFS, 5.8 vs. 3.7 months, P = 0.01) and EGFR-mutant NSCLC (median OS, 38.9 vs. 10.4 months, P < 0.01, and median PFS, 15.9 vs. 5.0 months, P < 0.01). Subsequent multivariate analyses detected high GRIm-Score in wild-type EGFR adenocarcinoma as a poor prognostic factor of OS (hazard ratio (HR) 2.20, 95% CI 1.47 - 3.31, P < 0.01), and in the EGFR-mutant NSCLC as a poor prognostic factor of PFS (HR 1.89, 95% CI 1.00 - 3.55, P = 0.049). CONCLUSIONS: High GRIm-Score was an independent prognostic biomarker of OS of first-line cytotoxic chemotherapy for wild-type EGFR adenocarcinoma and of PFS of first- or second-generation EGFR-TKI for EGFR-mutant NSCLC. Therefore, GRIm-Score is not only a specific selection marker for experimental immunotherapy trials, but may also be a promising and useful pretreatment prognostic maker for specific NSCLC subsets in the real-world practice.