Resection of positive tissue on methionine‐PET is associated with improved survival in glioblastomas

Abstract

Abstract Background and purpose The volume of excised tumor in contrast‐enhanced areas evaluated via magnetic resonance imaging is known to have a strong influence on the survival of patients with glioblastoma (GBM). In this study, we investigated the effect of tumor resection on the survival of patients with GBM in the 11C‐methionine (MET) accumulation area using MET‐positron emission tomography (MET‐PET). Methods A total of 26 patients (median age, 69 years; 15 males) who had undergone tumor resection and MET‐PET before and after surgery, after being newly diagnosed with GBM, were included in the study. MET‐PET before and after tumor resection were compared. The association between the decrease in the maximum standardized uptake value (SUV) of the tumor divided by the normal cortical mean SUV (%; ΔT/N), the MET extent of resection (MET‐EOR) from the % reduction in the MET accumulation area (%), and residual MET accumulation area (in cm3; MET‐residual tumor volume [RTV]), as well as the survival time of patients with GBM, were evaluated via univariate analysis. Results ΔT/N were positively associated with survival (hazard ratio [HR], 0.98 [95% confidence interval (CI), 0.97–0.99], p = .02). MET‐RTV revealed a negative association with survival (HR, 1.02 [95% CI, 1.01–1.04], p = .04). Additionally, MET‐EOR showed a strong trend with survival (HR, 0.99 [95% CI, 0.97–1.01], p = .06). Conclusions Surgical resection of MET‐accumulated areas in GBM significantly prolongs the survival of patients with GBM. However, a prospective large‐scale multicenter study is needed to confirm our findings.

Keywords

• 11C‐methionine
• extent of resection
• glioblastoma
• positron emission tomography
• survival