Abstract
Background In the glioma microenvironment, elevated immune cell ratios are posited to reflect systemic response to malignancy. Given the dearth in clinically significant molecular markers to predict prognosis, there is potential for immune cell ratios to serve as low-cost and readily available prognostic markers.
Objectives This study evaluated the ability for pretreatment peripheral immune cell ratios (Neutrophil-to-Lymphocyte Ratio, NLR, and Monocyte-to-Lymphocyte Ratio, MLR) to predict overall survival (OS) and modified Rankin Scale (mRS) at admission, 6 months and 12 months post-diagnosis. It also explored relationships between immune cell ratios and clinicopathological parameters (tumour location, tumour size, tumour grade, IDH-1 mutation, MGMT promoter methylation status).
Methods Pretreatment NLR and MLR were analysed retrospectively in 64 glioma patients from Royal Melbourne Hospital. OS was evaluated with the Kaplan-Meier method. Prognostic factors for OS and mRS were evaluated with univariate and multivariable regression analyses.
Results Higher pretreatment NLR (>4.7), compared to lower pretreatment NLR (≤4.7), predicted higher mean admission mRS (p<0.001) and 6-month mRS (p=0.02). Higher NLR was associated with poor functional outcome (mRS 3–6) at admission (p<0.001) and 6 months (p=0.001). Higher pretreatment MLR (>0.35) predicted poorer OS (p=0.02). Higher NLR was associated with larger tumour diameter (≥5cm) (p=0.02).
Conclusion To our knowledge, this was the first study to evaluate the association between immune cell ratios and mRS. This study demonstrated that NLR and MLR can serve as prognostic markers to predict functional outcomes and OS in glioma patients, which allows us to identify high-risk patients in need of further treatment.
