Long-term Overall Survival and Predictors in Anti-PD-1-naive Melanoma Patients With Brain Metastases Treated With Immune Checkpoint Inhibitors in the Real-world Setting: A Multicohort Study.

Long-term survival outcomes among melanoma patients with brain metastases treated with immune checkpoint inhibitors are limited. In this retrospective study at 2 centers, metastatic melanoma patients with radiographic evidence of brain metastases who received anti-programmed death-1 (PD-1) monotherapy or nivolumab in combination with ipilimumab between 2014 and 2017 were included. Overall survival (OS) was assessed in diagnosis-specific graded prognostic assessment (ds-GPA) and melanoma-molecular graded prognostic assessment (molGPA) prognostic risk groups. Baseline clinical covariates were used to identify predictors of OS in univariate/multivariable Cox proportional-hazards models. A total of 84 patients (58 monotherapy, 26 combination) were included with a median duration of follow-up of 43.4 months (maximum: 5.1 y). The median OS [95% confidence interval (CI)] was 3.1 months (1.8, 7) for ds-GPA 0-1, 22.1 months [5.4, not reached (NR)] for ds-GPA 2 and NR (24.9, NR) for ds-GPA 3-4 in the monotherapy cohort [hazard ratio (HR) for ds-GPA 3-4 vs. 0-1: 0.13 (95% CI: 0.052, 0.32); 0.29 (95% CI: 0.12, 0.63) for ds-GPA 2 vs. 0-1]. The median OS was 1.1 months (95% CI: 0.3, NR) for ds-GPA 0-1, 11.8 months (95% CI: 2.9, 23.3) for ds-GPA 2 and 24.4 months (95% CI: 3.4, NR) for ds-GPA 3-4 in the combination cohort [HR for 3-4 vs. 0-1: 0.013 (95% CI: 0.0012, 0.14); HR for ds-GPA 2 vs. 0-1: 0.033 (0.0035, 0.31)]. Predictors associated with longer survival included ds-GPA or molGPA>1 (among prognostic indices), neutrophil-to-lymphocyte ratio (<4 vs. ≥4), while high lactate dehydrogenase, neurological symptoms, and leptomeningeal metastases were associated with shorter survival. Baseline ds-GPA/molGPA>1 and neutrophil-to-lymphocyte ratio <4 were strong predictors of long-term survival to anti-PD-1-based immune checkpoint inhibitors in melanoma brain metastases patients previously naive to anti-PD-1 therapy in a real-world clinical setting treated at independent centers.