18F-FDOPA PET/MRI fusion in patients with primary/recurrent gliomas: initial experience.
OBJECTIVE
(18)F-FDOPA PET demonstrates higher sensitivity and specificity for gliomas than traditional [(18)F] FDG PET imaging. However, PET provides limited anatomic localization. The purpose of this study was to determine whether (18)F-FDOPA PET/MRI fusion can provide precise anatomic localization of abnormal tracer uptake and how this activity corresponds to MR signal abnormality.


METHODS
Two groups of patients were analyzed. Group I consisted of 21 patients who underwent (18)F-FDOPA PET and MRI followed by craniotomy for tumor resection. Group II consisted of 70 patients with a pathological diagnosis of glioma that had (18)F-FDOPA PET and MRI but lacked additional pathologic follow-up. Fused (18)F-FDOPA PET and MRI images were analyzed for concordance and correlated with histopathologic data.


RESULTS
Fusion technology facilitated precise anatomical localization of (18)F-FDOPA activity. In group I, all 21 cases showed pathology-confirmed tumor. Of these, (18)F-FDOPA scans were positive in 9/10 (90%) previously unresected tumors, and 11/11 (100%) of recurrent tumors. Of the 70 patients in group II, concordance between MRI and (18)F-FDOPA was found in 49/54 (90.1%) of patients with sufficient follow-up; in the remaining 16 patients concordance could not be determined due to lack of follow-up. (18)F-FDOPA labeling was comparable in both high- and low-grade gliomas and identified both enhancing and non-enhancing tumor equally well. In some cases, (18)F-FDOPA activity preceded tumor detection on MRI.


CONCLUSIONS
(18)F-FDOPA PET/MRI fusion provides precise anatomic localization of tracer uptake and labels enhancing and non-enhancing tumor well. In a small minority of cases, (18)F-FDOPA activity may identify tumor not visible on MRI.
Ledezma
Carlos J
CJ
Department of Radiological Sciences, David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA. ledezmacjl@gmail.com
Chen
Wei
W
Sai
Victor
V
Freitas
Bonnie
B
Cloughesy
Tim
T
Czernin
Johannes
J
Pope
Whitney
W
D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000175:diagnosis*; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives*; D005260:Female; D005910:Glioma / Q000175:diagnosis*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D010865:Pilot Projects; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique
D019275:Radiopharmaceuticals; C043437:fluorodopa F 18; D004295:Dihydroxyphenylalanine