Soft tissue metastases from differentiated thyroid cancer diagnosed by 18F FDG PET-CT

3 SUMMARY Distant metastases of differentiated thyroid cancer are unusual; lung and bones are the most frequently affected sites. Soft tissue metastases (STM) are extremely rare. We describe two ca- ses of patients with differentiated thyroid cancer metastasizing to soft tissues. Both patients had widespread metastatic disease; clinically asymptomatic soft tissue metastases were found by 18 -Fluordeoxyglucose positron emission tomography/computed tomography ( 18 F FDG PET-CT), and confirmed by cytological and/or histopathological studies. These findings underscore the ability of 18 F FDG PET-CT in accurately assessing the extent of the disease, as well as the utility of the method to evaluate regions of the body that are not routinely explored. Arq Bras Endocrinol