Different lesions revealed by 18F-FDG PET/CT and 18F-NaF PET/CT in patients with multiple myeloma.

We present different findings on 18F-FDG PET/CT and 18F-NaF PET/CT images in 2 patients with multiple myeloma. In 1 case, 18F-FDG PET/CT showed intense uptake in the lesions in the axial skeleton where 18F-NaF PET/CT seemed normal. In addition, a sternal lesion showed FDG uptake only in the center but NaF uptake only in the periphery. In another patient, intense NaF accumulation in a dorsal vertebra was noted, but the corresponding FDG uptake was unimpressive. The role of these 2 radioactive tracers in the management of multiple myeloma continues to be defined.