Imaging of brain tumor proliferative activity with iodine-131-iododeoxyuridine.

Abstract

METHODS: Iodine-131-iododeoxyuridine (IUdR) uptake and retention was imaged with SPECT at 2 and 24 hr after administering a 10-mCi dose to six patients with primary brain tumors. The SPECT images were directly compared to gadolinium contrast-enhanced MR images as well as to [18F]fluorodeoxyglucose (FDG) PET scans and 201Tl SPECT scans. RESULTS: Localized uptake and retention of IUdR-derived radioactivity was observed in five of six patients. The plasma half-life of [131I]IUdR was short (1.6 min) in comparison to the half-life of total plasma radioactivity (6.4 hr). The pattern of [131I]IUdR-derived radioactivity was markedly different in the 2-hr compared to 24-hr images. Radioactivity was l..