| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
|
|
|||||||||
|
|
Neurosciences: NeurologyImaging Malignant Brain Lesions |
1 Dept of Molecular and Medical Pharmacology; 2 Dept of Neuro-Oncology, UCLA David Geffen School of Medicine, Los Angeles, California
306
Objectives: To evaluate the metabolic changes during treatment using [18F]fluoro-L-dihydroxyphenylalanine (FDOPA) positron emission tomography (PET) in patients with recurrent malignant gliomas treated with bevacizumab (Avastin) and irinotecan.
Methods: 29 patients with recurrent malignant gliomas were prospectively studied with FDOPA-PET at baseline, at 2 weeks, and at 6 weeks after starting treatment. Tumor volume (Tvol) was obtained by including all voxels fall within mean SUV values of normal striatum isocontour. Mean and maximum FDOPA uptakes within this volume (SUVmean and SUVmax) were determined. Changes of Tvol and SUV were correlated with clinical outcomes.
Results: Following therapy, no significant declines of SUVs were seen (2weeks: 1.4%; 6weeks: 1.3%, P=0.90). Significant decreases in Tvol were seen at 2 weeks (-38.6%) and 6 weeks (-43.8%, P=0.03). Receiver operating characteristic curve analysis identified a 35% decrease of Tvol as the best criteria for metabolic response. Tvol changes at 2 weeks after starting treatment was predictive of tumor progression (P<0.0005) as well as of overall survival (P=0.023). Metabolic responders (n=18) had significantly longer time to progression (6.4 mo v 2.0 mo) and survival (10.7 mo v 6.7 mo) than non-responders (n=11). Tvol changes at 6 weeks was also predictive of progression (P=0.008) and showed a trend towards survival (P=0.078). In contrast, SUV changes were not predictive of progression or survival.
Conclusions: Tumor volume change by FDOPA-PET at 2 weeks after starting therapy is predictive of tumor progression and overall survival for patients with recurrent malignant gliomas.
| ||||||||||||||||||||||||||||||||||||||
