Findings of Pulmonary Amyloidosis on Dual Phase FDG PET/CT Imaging

A 50-year-old asymptomatic woman underwent dual phase FDG PET/CT to evaluate bilateral lung masses which were seen on routine chest radiographs. The PET/CT images at 1 hour during the early phase showed increased FDG activity in the lung masses, which initially were suggestive of malignant lesions. However, in the 2 hour delayed phase of the images, the metabolic activity of the lesions decreased compared with the earlier phase, which indicated that the lesions were more likely to have a benign etiology. The subsequent biopsy demonstrated that the lung masses were pulmonary amyloid lesions.