Sarcoidosis Demonstrated by FDG PET Imaging With Negative Findings on Gallium Scintigraphy

Abstract
The manifestations of sarcoidosis are protean and have been well described. Conventionally, gallium-67 scan is used to evaluate sarcoidosis in nuclear medicine. Fluorodeoxyglucose positron emission tomography (FDG PET) has been successfully used in the evaluation of cancers. However, FDG is not a tumor-specific radiotracer and can also accumulate in the sarcoid lesions. We present a case of sarcoidosis, which demonstrated an unremarkable gallium-67 scintigraphy but showed extensive FDG uptake in the chest and the brain on PET imaging.