The Clinical Frailty Scale as predictor of overall survival after resection of high-grade glioma

BACKGROUND: The Clinical Frailty Scale (CFS) describes the general level of fitness or frailty and is widely used in geriatric medicine, intensive care and orthopaedic surgery. This study was conducted to analyze, whether CFS could be used for patients with high-grade glioma. METHODS: Patients harboring high-grade gliomas, undergoing first resection at our center between 2015 and 2020 were retrospectively evaluated. Patients’ performance was assessed using the Rockwood Clinical Frailty Scale and the Karnofsky Performance Scale (KPS) preoperatively and 3–6 months postoperatively. RESULTS: 289 patients were included. Pre- as well as postoperative median frailty was 3 CFS points (IqR 2–4) corresponding to “managing well”. CFS strongly correlated with KPS preoperatively (r = − 0.85; p < 0.001) and at the 3–6 months follow-up (r = − 0.90; p < 0.001). The reduction of overall survival (OS) was 54% per point of CFS preoperatively (HR 1.54, CI 95% 1.38–1.70; p < 0.001) and 58% at the follow-up (HR 1.58, CI 95% 1.41–1.78; p < 0.001), comparable to KPS. Patients with IDH mutation showed significantly better preoperative and follow-up CFS and KPS (p < 0.05). Age and performance scores correlated only mildly with each other (r = 0.21…0.35; p < 0.01), but independently predicted OS (p < 0.001 each). CONCLUSION: CFS seems to be a reliable tool for functional assessment of patients suffering from high-grade glioma. CFS includes non-cancer related aspects and therefore is a contemporary approach for patient evaluation. Its projection of survival can be equally estimated before and after surgery. IDH-mutation caused longer survival and higher functionality.