gms | German Medical Science

60th Annual Meeting of the German Society of Neurosurgery (DGNC)
Joint Meeting with the Benelux countries and Bulgaria

German Society of Neurosurgery (DGNC)

24 - 27 May 2009, Münster

Comparison of FET PET and FDG PET in brain tumors

Meeting Abstract

  • M.C. Sabel - Neurochirurgische Klinik, Universitätsklinikum Düsseldorf
  • G. Stoffels - Institut für Neurowissenschaften und Biophysik 3, Forschungszentrum Jülich
  • D. Pauleit - Institut für Neurowissenschaften und Biophysik 3, Forschungszentrum Jülich
  • F. Floeth - Neurochirurgische Klinik, Universitätsklinikum Düsseldorf
  • A. Bachofner - Nuklearmedizinische Klinik, Universitätsklinikum Düsseldorf
  • K.J. Langen - Institut für Neurowissenschaften und Biophysik 3, Forschungszentrum Jülich

Deutsche Gesellschaft für Neurochirurgie. 60. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit den Benelux-Ländern und Bulgarien. Münster, 24.-27.05.2009. Düsseldorf: German Medical Science GMS Publishing House; 2009. DocDI.09-05

DOI: 10.3205/09dgnc171, URN: urn:nbn:de:0183-09dgnc1718

Published: May 20, 2009

© 2009 Sabel et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Outline

Text

Objective: The purpose of this study was to compare the diagnostic value of Positron Emission Tomography (PET) using 18F-Fluordeoxglucose (FDG) and O-(2-[F-18]fluoroethyl)-L-tyrosine (FET) in patients suspected of having cerebral gliomas.

Methods: Forty-three patients with suspected cerebral gliomas (34 primary tumors, 9 recurrences) were included in this study. After injection of FET, a first PET scan (FET scan) was performed. Thereafter, FDG was injected and a second PET scan was acquired from 30 to 60 min after the 2nd injection (FET/FDG scan). The cerebral accumulation of FDG was calculated by decay corrected subtraction of the FET scan from the FET/FDG scan. Tracer uptake was evaluated by visual scoring and by lesion to background ratios (L/B). The imaging results were compared with the histological results and prognosis (follow-up 3–4 years).

Results: Histology revealed 24 low-grade gliomas (LGG) and 19 high-grade gliomas (HGG). The gliomas showed increased FET uptake (>gray matter) in 83% and increased FDG uptake (>white matter) in 51%. The delineation of the extent of the tumour was possible with FET PET only. A local maximum in the tumour area for biopsy guidance could be identified with FET in 77% and with FDG in 28%. The maximum was identical for both tracers in all but one glioma. The L/B ratios and visual scoring showed significant differences between LGG and HGG for both tracers but considerable overlap, so that an individual diagnosis was crucial. A prognostic significance for primary tumours was found for FDG uptake (p=0.03) but not for FET uptake.

Conclusions: FET PET is superior to FDG for biopsy guidance and treatment planning of cerebral gliomas. The uptake of both tracers shows a significant correlation with tumour grade and some prognostic impact for FDG PET. The predictive value, however, is limited and a biopsy remains necessary. Amino acids like FET are the single PET tracers of choice for the diagnosis of cerebral gliomas.