Pt. Meyer et al., High F-18FDG uptake in a low-grade supratentorial ganglioglioma - A positron emission tomography case report, CLIN NUCL M, 25(9), 2000, pp. 694-697
Purpose: Positron emission tomography (PET) with fluorine-18 fluorodeoxyglu
cose (F-18 FDG) is used for the noninvasive monitoring and grading of prima
ry brain tumors. Here the FDG uptake is positively correlated with the mali
gnant extent of the lesion and thereby negatively correlated with patient s
urvival. Little is known about the FDG PET features of primary brain tumors
in children, such as mixed neuronal-glial tumors,
Methods: The authors describe a 13-year-old boy who had partial complex sei
zures since early childhood caused by a brain tumor in the left temporal ro
be.
Results: Magnetic resonance and computed tomographic examinations yielded u
ncharacteristic results: mixed density, marked calcifications, little contr
ast enhancement, a nearly absent mass effect, and no edema. The FDG PET sca
n revealed a large hypermetabolic tumor, with a tumor: contralateral gray m
atter FDG uptake ratio of 1.45, In contrast to this intense hypermetabolism
, the pathologic analysis after gross total resection revealed a low-grade
ganglioglioma (WHO grade I), which is usually associated with an excellent
prognosis,
Conclusions: Mixed neuronal-glial tumors such as gangliogliomas must be con
sidered in making differential diagnoses by judging hypermetabolic FDG PET
scans in young patients with brain tumors in the presence of uncharacterist
ic imaging features.