Value of MRI enhanced voxel subtraction technique in prognostic assessment for recurrent glioblastoma

Objective To investigate the values of enhancing tumor volume (V), total volume (Vn) and relative non-enhancing tumor ratio (rNTR) before second-line treatment on overall survival (OS) and post-recurrence survival (PRS) in recurrent glioblastoma (rGBM). Methods Clinical data of 85 patients with confirmed rGBM admitted in our medical center from July 2012 to December 2022 were collected and retrospectively analyzed. Quantitative measurements of V, Vn (including tumor enhancement, necrotic and cystic volume) and rNTR (FLAIR high signal volume/enhancing tumor volume) were performed with T1-weighted imaging (T1WI) subtraction mode. Kaplan-Meier survival curve and log-rank test were used to analyze the differences of prognosis between high and low level groups of above indicators. Cox proportional risk regression model was employed for univariate and multivariate prognostic analyses. Results The median PRS was 238 d (95%CI: 197.472~278.528) and the median OS was 449 d (95%CI: 348.755~549.245) in these patients. Ka