Association between GRIm score and response to nivolumab monotherapy in patients with advanced malignant melanoma

BACKGROUND/OBJECTIVES: Malignant melanoma is an aggressive skin cancer with significant metastatic potential. Immune checkpoint inhibitors (ICIs), particularly those targeting the PD-1 pathway, have revolutionized treatment, improving survival rates. A PD-1 inhibitor, Nivolumab, has demonstrated durable responses in advanced melanoma patients. However, response variability necessitates predictive biomarkers for patient stratification. METHODS: The Gustave Roussy Immune Score (GRIm Score) is a prognostic tool integrating lactate dehydrogenase (LDH), neutrophil-to-lymphocyte ratio (NLR), and albumin levels to predict ICI efficacy. This retrospective study evaluated the association between the GRIm Score and response to nivolumab monotherapy in 40 patients with stage IV malignant melanoma treated between 2020 and 2024. Patients were classified into low-risk (score 0-1) and high-risk (score 2-3) groups. RESULTS: Results showed that patients with a low GRIm Score had significantly longer median progression-free survival (21.4 vs. 6.3 months, p = 0.003) and overall survival (26.5 vs. 7.2 months, p < 0.001). Multivariate analysis confirmed the GRIm Score as an independent prognostic factor (HR: 1.593, 95% CI: 1.156-2.197, p = 0.004), surpassing the predictive power of its components. CONCLUSIONS: This study is the first to validate the GRIm Score in malignant melanoma, suggesting it is a valuable biomarker for patient selection in immunotherapy trials. The findings highlight its potential in refining treatment decisions, though further validation in larger, multicenter cohorts is required.