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

Differentiating high vs. low grade gliomas using FET-PET in the presurgical assessment

Meeting Abstract

  • J. Nickel - Neurologische Klinik, Universitätsklinikum Düsseldorf
  • Y. Hamzavi - Neurologische Klinik, Universitätsklinikum Düsseldorf
  • G. Stoffels - Institute for Neuroscience & Biophysics, Research Center Jülich
  • K.J. Langen - Institute for Neuroscience & Biophysics, Research Center Jülich
  • R. Seitz - Neurologische Klinik, Universitätsklinikum Düsseldorf
  • M. Sabel - Klinik für Neurochirurgie, Universitätsklinikum Düsseldorf

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. DocP02-06

DOI: 10.3205/09dgnc266, URN: urn:nbn:de:0183-09dgnc2669

Published: May 20, 2009

© 2009 Nickel et al.
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Outline

Text

Objective: Amino acid tracers are being widely used in the presurgical evaluation of gliomas and possess good sensitivity and specifity to outline vital tumor tissue. However, the predictive potential of O-(2-[18F]fluoroethyl)-L-tyrosine positron emission tomography (FET-PET) regarding the biological grading of a given tumor is still under investigation.

Methods: In 29 patients with gliomas (high resolution T1-MRI ± contrast agent, FET-PET) we used multiple quantitative analyses of the FET-PET images obtained both dynamically after injection of a 200MBq Bolus of FET as well as statically during the steady state after injection. Variables were calculated as mean and maximum tumor to brain ratio using the healthy hemisphere as control (TBR), uptake volume (above a TBR of 1.6 in ml, using an exact voxel-based volumetry) and kinetics (low-grade vs. intermediate vs. high-grade kinetics) of the FET-PET, tumor volume (based on T1-weighted MR images), volume of contrast agent enhancement (if present), and cellular markers of progression in the resected specimen or biopsy of 18 patients (expression of p53, Ki67, WHO grading). A multivariate correlation analysis was performed using raw and grouped values.

Results: Volumetry and uptake kinetics, but not TBR-analysis of FET PET-uptake in gliomas were significantly correlated with biomarkers of progression (FET uptake volume vs. expression of Ki67, Kendall tau-b 0.498, p=0.004 and Spearmann-rho 0.615, p=0.007; kinetics vs. Expression of Ki67, Kendall Tau-b 0.498, p=0.014 and Spearmann-rho 0.588, p=0.13) and higher WHO grades (FET uptake volume vs. WHO grade with Spearmann-rho 0.565 and Kendall Tau-b 0.686, each p<0.001; kinetics vs. WHO grade, Kendall Tau-b 0.612, p=0.002 and Spearmann-rho 0.665, p<0.001) of gliomas. Notably, there was no suitable information given by the quantitative assessment of standard MR contrast agent uptake or the p53-expression in this series (no significant correlations with neuropathological variables).

Conclusions: The exact volumetric as well as the kinetic analysis of FET-PET improves the presurgical evaluation of gliomas and allows for a better prediction of the WHO grading. Thus these approaches may help to provide suitable prognoses and decisions concerning surgical versus conservative treatment in individual patients. These data support a recommendation for a wider use of amino acid PET in the presurgical assessment of gliomas.