Phase 2 Study on Brain Tumor Uptake of the Amino Acid O-(2-[F-18]Fluorethyl)-L-Tyrosin (FET)
Radioactively labelled amino acids have been used for years to delineate primary brain
tumors and for the early detection of tumor recurrence. Positron emission tomography studies
indicate that the extent of amino acid uptake correlates to the true histological extent of
gliomas. Recently a fluorine-18 labelled amino acid has been introduced
(O-(2-[F-18]Fluorethyl)-L-tyrosin (FET)), which is suitable for routine use in brain tumor
patients. There is evidence that this amino acid is transported into brain and brain tumors
by the amino acid transport of the L-type. The cDNA of this L-transporter has recently been
cloned and has been shown to be identical to the light chain of the 4F2-antigen (CD98),
which has previously been described as marker of cell growth and proliferation.
The heavy chain of this heterodimer is known to modulate integrins which are thought to play
a fundamental role in glioma invasion.
Besides the evaluation of the diagnostic capability of FET in brain tumors, a comparison of
FET uptake in vivo and CD98 expression ex-vivo is performed with tissue slices as available
after routine surgery in glioma patients.
Allocation: Non-Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic
Histological samples where available
Matthias Weckesser, MD
Department of Nuclear Medicine, University Hospital Muenster
Germany: Federal Institute for Drugs and Medical Devices