Detection of osseous metastasis by [۶۸Ga]Ga-FAPI PET/CT in a thyroid cancer patient with elevated thyroglobulin and negative radioiodine scintigraphy

Thyroglobulin elevated-negative iodine scintigraphy (TENIS) differentiated thyroid cancer (DTC) patients are a subgroup of DTC patients with almost rapid disease progression and reduced overall survival and them usually do not have an effective treatment modality. Surgery and metastatectomy is the best option for recurrent disease in cases of solitary or oligometastasis. Detection of the metastatic sites is of utmost importance in these patients. We present a patient with TENIS syndrome and negative [۱۸F]FDG PET/CT and [۶۸Ga]Ga-DOTATATE whole body PET/CT scan in whom just [۶۸Ga]Ga-FAPI PET/CT helped in localizing the metastatic lesion to the iliac bone and subsequently the bone metastasis was resected and the pathology report confirmed the diagnosis.