18F-NaF

18F-NaF PET/CT is a well-established and validated imaging tool for imaging skeletal system. The bio-distribution represents blood flow that varies among different bones; due to urinary excretion, bladder and kidneys can be normally visualized. The role of this tracer has been well demonstrated in imaging bone metastases, with sensitivity superior to 18F-FDG PET/CT and other conventional imaging modalities. In particular, 18F-NaF PET/CT can detect bone malignant involvement before lesions can be radiologically documented; however, a lack of specificity should be considered, due to the possibility of uptake in benign diseases as calcium deposits in brain and large arteries, osteoarthritis, and post-traumatic lesions. Beyond oncology, this tracer can play a role in forensic use, evaluation of skeletal benign diseases and atherosclerotic plaque. 18F-NaF uptake is also documented in meningioma, rheumatoid arthritis, amyloidosis, and lymphomas. Globally, nuclear medicine physicians must take into account the possibility of 18F-NaF uptake in all calcifications that can occur in benign or malignant diseases.