Thyroid Follicular Carcinoma with Iodine-Avid Bone Metastases Showing Mild Uptake on Both 18 F-FDG and 68 Ga-DOTATOC PET/CT

Differentiated thyroid carcinoma (DTC) is usually characterized by good prognosis. Radioiodine scan is the first-line diagnostic tool to detect the metastatic disease. In patients with high Tg levels suggesting metastatic disease when radioiodine scan is negative, 18F-fluorodeoxyglucose positron emission tomography/computerized tomography (FDG PET/CT) is reported to be effective in defining the metastatic foci. Another imaging modality is somatostatin receptor imaging with PET/CT which can be used especially when 18F-FDG PET/CT is nondiagnostic. Peptide receptor radionuclide therapy with β-emitting radionuclides may be considered when somatostatin positivity is defined in metastatic lesions. In this case report, a patient with DTC having radioiodine-positive bone metastases showing mild uptake in 18F-FDG PET/CT and 68Ga-DOTATOC PET/CT is presented.