A 53 y.o. right handed man sought medical attention because of a grand mal seizure.
Brain biopsy revealed grade IV astrocytoma.
The MR demonstrates an area of mixed signal intensity on
proton density (PD) and T2-weighted (T2) images in
a right parietal-occipital region. The central rounded
core of the lesion is seen after contrast enhancement to
contain cystic elements. Glucose metabolism is very low on the
first PET study, but has increased three months later.
This suggests tumor recurrence, and effectively rules out radiation
Like Thallium SPECT, the PET scan has been very useful in differentiating tumor recurrence and radiation necrosis. It also allows specific targeting of the area of recurrence, which may be surrounded by radiation necrosis in those patients who have received radiation.
Case contributed by Drs. C. D. Sturm and R. Bucholz, St. Louis University.