VALUE OF FLUORINE-18-FLUORODEOXYGLUCOSE AND TL-201 IN THE DETECTION OF PANCREATIC-CANCER

This study compares the diagnostic value of F-18-FDG PET imaging and T l-201-SPECT imaging in patients with pancreatic cancer. Methods: Twent y-five patients with histologically-proven pancreatic cancer were stud ied. Following PET transmission scanning, 3 mCi of Tl-201 were adminis tered after patients had fasted overnight. Thallium-201-SPECT images w ere obtained 15 min later. Immediately after Tl-201-SPECT imaging, 4 m Ci of FDG were administered and PET images were obtained 60 min later. The PET and SPECT images were compared qualitatively and quantitative ly. For quantitative analysis, 10 x 10 mm(2) regions of interest (ROIs ) were selected in areas of the tumor showing the highest tracer accum ulation and in the normal pancreas. The tumor to nontumor activity rat io (T/N ratio) was calculated. Results: Although both techniques delin eated focal lesions with an increase in tracer accumulation in 16 pati ents, PET identified eight additional patients in whom Tl-201-SPECT im ages did not visualize any lesion. Thus, FDG-PET provided significantl y higher sensitivity (96%) than Tl-201-SPECT (64%). Among the patients showing increased tracer accumulation, the T/N ratio was significantl y higher with FDG-PET (3.24 +/- 1.27) than with Tl-201-SPECT (1.77 +/- 0.37) (p < 0.0001). Conclusion: We conclude that FDG-PET has a larger clinical value for noninvasive detection of pancreatic cancer than Tl -201-SPECT. If a PET camera is available, FDG-PET is considered to be the method of choice for the evaluation of patients with suspected pan creatic cancer.