Publication
MRI and FET-PET Predict Survival Benefit from Bevacizumab Plus Radiotherapy in Patients with Isocitrate Dehydrogenase Wild-type Glioblastoma: Results from the Randomized ARTE Trial
Journal Paper/Review - Sep 23, 2020
Wirsching Hans-Georg, Tabatabai Ghazaleh, Ochsenbein Adrian, Roth Patrick, Remonda Luca, Conen Katrin, Caparrotti Francesca, von Moos Roger, Hottinger Andreas F, Hundsberger Thomas, Weller Jonathan, Roelcke Ulrich, Weller Michael
Units
PubMed
Doi
Citation
Type
Journal
Publication Date
Issn Electronic
Pages
Brief description/objective
PURPOSE
To explore a prognostic or predictive role of MRI and O-(2-F-fluoroethyl)-L-tyrosine (FET) PET parameters for outcome in the randomized multicenter trial ARTE that compared bevacizumab plus radiotherapy with radiotherpay alone in elderly patients with glioblastoma.
PATIENTS AND METHODS
Patients with isocitrate dehydrogenase wild-type glioblastoma ages 65 years or older were included in this analysis. Tumor volumetric and apparent diffusion coefficient (ADC) analyses of serial MRI scans from 67 patients and serial FET-PET tumor-to-brain intensity ratios (TBRs) from 31 patients were analyzed blinded for treatment arm and outcome. Multivariate Cox regression analysis was done to account for established prognostic factors and treatment arm.
RESULTS
Overall survival benefit from bevacizumab plus radiotherapy compared with radiotherapy alone was observed for larger pretreatment MRI contrast-enhancing tumor [HR per cm 0.94; 95% confidence interval (CI), 0.89-0.99] and for higher ADC (HR 0.18; CI, 0.05-0.66). Higher FET-TBR on pretreatment PET scans was associated with inferior overall survival in both arms. Response assessed by standard MRI-based Response Assessment in Neuro-Oncology criteria was associated with overall survival in the bevacizumab plus radiotherapy arm by trend only ( = 0.09). High FET-TBR of noncontrast-enhancing tumor portions during bevacizumab therapy was associated with inferior overall survival on multivariate analysis (HR 5.97; CI, 1.16-30.8).
CONCLUSIONS
Large pretreatment contrast-enhancing tumor mass and higher ADCs identify patients who may experience a survival benefit from bevacizumab plus radiotherapy. Persistent FET-PET signal of no longer contrast-enhancing tumor after concomitant bevacizumab plus radiotherapy suggests pseudoresponse and predicts poor outcome.