68Ga-Dotatate PET/CT on the Follow-up of Patients with Medullary Thyroid Carcinoma

The purpose of this study is to evaluate the impact of 68Ga-DOTATE PET/CT on the management of medullary thyroid carcinoma (MTC). Eighteen patients (9 males and 9 females) with MTC who underwent 68Ga-DOTATE PET/CT for elevated calcitonin(Ct) levels were included in this study. Histopathological data, laboratory findings, 68Ga-DOTATE PET/CT findings were evaluated for each patient. 68Ga-DOTATATE PET/CT imaging findings were negative in 5 of 18 patients (27.8%) and positive in 13 of 18 patients (72.2%). The mean Ct level of patients with positive findings was higher than others. 68Ga-DOTATATE PET/CT was insufficient for detecting liver metastases in two patients who exhibited hypermetabolic uptakes consistent with solitary metastases in the liver on 18FDG-PET/CT. We believe that 68Ga-DOTATATE PET/CT plays an important role in the management of MTC patients with recurrent or metastatic disease. Its sensitivity is directly proportional to the levels of serum Ct. However, it may have limitations in detecting liver metastases.