Red blood cell distribution width to platelet ratio substantiates preoperative survival prediction in patients with newly-diagnosed glioblastoma

OBJECT: The conception of individual patient-adjusted treatment strategies is constantly emerging in the field of neuro-oncology. Systemic laboratory markers may allow insights into individual needs and estimated treatment benefit at an earliest possible stage. Therefore, the present study was aimed at analyzing the prognostic significance of preoperative routine laboratory values in patients with newly-diagnosed glioblastoma. METHODS: Between 2014 and 2019, 257 patients were surgically treated for newly-diagnosed glioblastoma at the Neuro-Oncology Center of the University Hospital Bonn. Preoperative routine laboratory values including red blood cell distribution width (RDW) and platelet count were reviewed. RDW to platelet count ratio (RPR) was calculated and correlated to overall survival (OS) rates. RESULTS: Median preoperative RPR was 0.053 (IQR 0.044–0.062). The receiver operating characteristic (ROC) curve indicated an optimal cut-off value for RPR to be 0.05 (AUC 0.62; p = 0.002, 95% CI 0.544–0.685). 101 patients (39%) presented with a preoperative RPR < 0.05, whereas 156 patients (61%) had a RPR ≥ 0.05. Patients with preoperative RPR < 0.05 exhibited a median OS of 20 months (95% CI 17.9–22.1), which was significantly higher compared to a median OS of 13 months (95% CI 10.9–15.1) in patients with preoperative RPR ≥ 0.05 (p < 0.001). CONCLUSIONS: The present study suggests the RPR to constitute a novel prognostic inflammatory marker for glioblastoma patients in the course of preoperative routine laboratory examinations and might contribute to a personalized medicine approach.