Diagnostic Accuracy of PET for Recurrent Glioma Diagnosis: A Meta-Analysis

BACKGROUND AND PURPOSE: Studies have assessed PET by using various tracers to diagnose disease recurrence in patients with previously treated glioma; however, the accuracy of these methods, particularly compared with alternative imaging modalities, remains unclear. Weconducted a meta-analysis to quantitatively synthesize the diagnostic accuracy of PET and compare it with alternative imaging modalities. MATERIALS AND METHODS: We searched PubMed and Scopus (until June 2011), bibliographies, and review articles. Two reviewers extracted study characteristics, validity items, and quantitative data on diagnostic accuracy. Weperformed meta-analysis when >= 5 studies were available. RESULTS: Twenty-six studies were eligible. Studies were heterogeneous in treatment strategies and diagnostic criteria of PET; recurrence was typically suspected by CT or MR imaging. The diagnostic accuracies of F-18-FDG (n = 16) and C-11-MET PET (n = 7) were heterogeneous across studies. F-18-FDG PET had a summary sensitivity of 0.77 (95% CI, 0.66-0.85) and specificity of 0.78 (95% CI, 0.54-0.91) for any glioma histology; C-11-methionine PET had a summary sensitivity of 0.70 (95% CI, 0.50-0.84) and specificity of 0.93 (95% CI, 0.44-1.0) for high-grade glioma. These estimates were stable in subgroup and sensitivity analyses. Data were limited on F-18-FET (n = 4), F-18-FLT (n = 2), and F-18-boronophenylalanine (n = 1). Few studies performed direct comparisons between different PET tracers or between PET and other imaging modalities. CONCLUSIONS: F-18-FDG and C-11-MET PET appear to have moderately good accuracy as add-on tests for diagnosing recurrent glioma suspected by CT or MR imaging. Studies comparing alternative tracers or PET versus other imaging modalities are scarce. Prospective studies performing head-to-head comparisons between alternative imaging modalities are needed.