Attenuation artifact from sclerotic bone can mimic active bone metastasis on PET-CT.

We report the PET-CT appearance of sclerotic bone mimicking active bone metastasis in a 57-year-old woman with right breast cancer and bone and hepatic metastases. Hybrid PET-CT was performed 1 month after completion of surgery and chemoradiation treatment. PET-CT demonstrated hypermetabolic foci in the right pulmonary hilum and liver. Increased hypermetabolic activity in L1 and L3 vertebral bodies was also seen corresponding to sclerotic vertebral bodies on CT study. The activity in L1 and L3 vertebral bodies was not visualized on nonattenuation-corrected images, consistent with an attenuation correction artifact resulting from extensive sclerosis in these regions.