Comparison of F-18 FET-PET with F-18 FDG-PET for biopsy planning of non-contrast-enhancing gliomas.
OBJECTIVE
The management of non-contrast-enhancing brain tumours largely depends on biopsy, which allows a differentiation of low-grade gliomas (LGG) from high-grade gliomas (HGG). The aim of this study was to compare positron emission tomography using 2-[(18)F]-fluoro-2-deoxy-D: -glucose (FDG-PET) and O-(2-[(18)F]-fluoroethyl)-L: -tyrosine (FET-PET) in terms of providing target regions for biopsies.


METHODS
Fifteen consecutive patients with newly diagnosed brain tumours (n = 11) or suspected recurrence of a known LGG (n = 4), in whom MRI demonstrated no contrast enhancement, were studied by both FET-PET and FDG-PET. FET-PET, FDG-PET and MRI data were fused, and then transferred to the neurosurgical navigation system, prior to neurosurgical interventions.


RESULTS
Histology showed HGG (WHO grade III) in 6/15 and LGG (WHO grade II) in 9/15 patients. FET-PET revealed an increased intratumoural tracer uptake in 8/9 LGG and in 5/6 HGG. FDG-PET depicted hypermetabolic spots in 2/9 LGG and in 4/6 HGG. In 6 patients we observed an increased intratumoural uptake of both tracers. In 4 of them, the area of highest FET accumulation in the tumour corresponded to the focus of increased FDG uptake.


CONCLUSIONS
FET-PET appears to be superior to FDG-PET for biopsy planning in non-contrast-enhancing brain tumours. FDG-PET does not provide any additional information in this issue.
Department of Nuclear Medicine, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany. michail.plotkin@charite.de
Michail
M
Plotkin
C
C
Blechschmidt
G
G
Auf
F
F
Nyuyki
L
L
Geworski
T
T
Denecke
W
W
Brenner
F
F
Stockhammer
D000328:Adult; D000368:Aged; D001706:Biopsy / Q000379:methods; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media / Q000494:pharmacology*; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000494:pharmacology*; D005910:Glioma / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods; D011379:Prognosis; D012008:Recurrence; D016896:Treatment Outcome; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000494:pharmacology
D003287:Contrast Media; D019788:Fluorodeoxyglucose F18; C545932:(18F)fluoroethyltyrosine; D014443:Tyrosine