Radiology 1993 Jan;186(1):37-44
Brain metastases from non-central nervous system tumors: evaluation with PET.
Griffeth LK, Rich KM, Dehdashti F, Simpson JR, Fusselman MJ, McGuire AH, Siegel
BA.
Positron emission tomography (PET) with fluorine-18 fluorodeoxyglucose (FDG) was
performed in 19 patients with brain metastases from non-central nervous system
(CNS) neoplasms and one patient with a primary CNS lymphoma. Various
histopathologic types were represented by the primary neoplasms in the patients
with metastases. Only 21 of the 31 lesions (68%) were detected with FDG PET as
discrete, metabolically active foci (relative to surrounding structures). Six of
the nondetected lesions may have been nondiscernible owing to their small size
and/or isointensity relative to closely apposed normal gray matter. However,
four lesions of at least 1.2 cm in diameter showed frankly decreased FDG
accumulation relative to normal brain. These findings suggest that studies of
FDG accumulation by a variety of non-CNS neoplasms and their CNS metastases are
in order and that extrapolation of the successes of FDG PET in imaging of
primary glial tumors to imaging of brain metastases should proceed with caution.