The Prognostic value of pretreatment gallium-68 DOTATATE positron emission tomography/computed tomography in irradiated non-benign meningioma

The purpose of this study was to evaluate the potential value of gallium-68 (Ga-68)-DOTATATE positron emission tomography/computed tomography (PET/CT) in predicting the risk of progression in non-benign meningioma after definite irradiation. We retrospectively reviewed our patients with meningiomas who had the highest risk of progression: WHO histological Grade II and III tumors and with macroscopic disease as identified in Ga-68-DOTATATE PET/CT. Thirteen patients were included in this study. For each tumor, the following quantifiers were measured: maximum and mean standardized uptake volume (SUV), standard deviation, metabolic tumor volume (MTV), total lesion activity, and coefficient of variation. Each of the quantifiers except for maximum SUV was obtained with three different SUV thresholds: muscle based (ms), liver based (liv), and gradient based (gb). The quantifiers were analyzed in univariate Cox model for their prognostic value for progression-free survival (PFS) and overall survival (OS). Mean follow-up of the patients was 28.2 months. The 2-year PFS and OS was 28.1% and 76.9%, respectively. The MTVgb was a significant predictor for PFS (risk of progression of disease above vs. below the 34 cm³ threshold: 100% vs. 28.3%,P = 0.0003). Clinically, the male sex also influenced PFS (Hazard ratio =13.06; 95% confidence interval: 1.56–109.25;P = 0.018). The mean SUVms(P = 0.041) and SUVgb(P = 0.048) had a prognostic value for predicting the risk of death. Ga-68-DOTATATE PET/CT has potential to predict disease progression in nonbenign meningioma patients. Further prospective studies for validating and standardizing these findings are indicated. (author)