Dynamic (18F)-2-fluoro-2-deoxy-D-glucose (FDG) scintigraphy of normal and tumor-bearing rats

Five normal rats, 14 rats bearing the Rous sarcoma intrarenally, and four rats with DMBA-induced mammary carcinomas were imaged by dynamic (18F)-2-fluoro-2-deoxy-D-glucose ((18F)FDG) scintigraphy and (99mTc)DTPA renography. The brain, heart, liver, kidneys, and tumor were selected as regions of interest (ROI) for time activity curves; exponential functions were fitted to the decay-corrected curves, which yielded biologic half-lives of (18F)FDG in the ROI. It was found that all organs ROI's exhibited average elimination of activity, whereas activity accumulated in the tumor ROI for the duration of the study (5h). The (99mTc)DTPA renographies showed that the excretory function in kidneys bearing the Rous sarcoma is severely impaired. This study shows that small laboratory animals can be successfully scintigraphied with a conventional gamma camera using (18F)FDG and that the pharmacokinetics of this radiopharmaceutical may be evaluated.