Differentiated Thyroid Cancer: A New Perspective with Radiolabeled Somatostatin Analogues for Imaging and Treatment of Patients

作者:Versari Annibale; Sollini Martina*; Frasoldati Andrea; Fraternali Alessandro; Filice Angelina; Froio Armando; Asti Mattia; Fioroni Federica; Cremonini Nadia; Putzer Daniel; Erba Paola Anna
来源:Thyroid, 2014, 24(4): 715-726.
DOI:10.1089/thy.2013.0225

摘要

Background: The expression of somatostatin receptors (SSTR) in thyroid cells may offer the possibility to identify metastatic lesions and to select patients for peptide receptor radionuclide therapy (PRRT). We investigated Ga-68-DOTATOC positron emission tomography/computed tomography (PET/CT) to select patients with progressive differentiated thyroid cancer (DTC) for PRRT as well as treatment response and toxicity in treated patients. %26lt;br%26gt;Methods: We enrolled 41 patients with progressive radioiodine-negative DTC (24 women and 17 men; mean age=54.3 years, median=59 years, range=19-78 years). In all patients, [F-18]FDG-PET/CT was performed to determine recurrent disease with enhanced glucose metabolism, and Ga-68-DOTATOC PET/CT was used to identify SSTR expression. Dosimetric evaluation was performed with In-111-DOTATOC scintigraphy. Eleven patients were treated with PRRT receiving a fractionated injection of 1.5-3.7 GBq Y-90-DOTATOC/administration. Serial Ga-68-DOTATOC PET/CT scans were performed in all treated patients to evaluate treatment response. Parameters provided by Ga-68-DOTATOC PET/CT were analyzed as potential therapeutic predictors to differentiate responding from nonresponding. In all treated patients, adverse events and toxicity were recorded. %26lt;br%26gt;Results: Ga-68-DOTATOC PET/CT were positive in 24/41 of radioiodine-negative DTC patients. Based on the high expression of SSTR detected by Ga-68-DOTATOC PET/CT, 13 patients were suitable for PRRT. Two out of 13 patients were not treated due to the lack of fulfillment of other study inclusion criteria. PRRT induced disease control in 7/11 patients (two partial response and five stabilization) with a duration of response of 3.5-11.5 months. Objective response was associated with symptoms relief. Functional volume (FV) over time obtained by PET/CT was the only parameter demonstrating a significant difference between lesions responding and nonresponding to PRRT (p=0.001). Main PRRT adverse events were nausea, asthenia, and transient hematologic toxicity. One patient experienced permanent renal toxicity. %26lt;br%26gt;Conclusions: In our series, SSTR imaging provided positive results in more than half of the cases with radioiodine-negative DTC, and about one third of patients were eligible for PRRT. Ga-68-DOTATOC PET/CT seems a reliable tool both for patient selection and evaluation of treatment response. In our experience, FV determination over time seems to represent a reliable parameter to determine tumor response to PRRT, although further investigations are needed to better define its role.

  • 出版日期2014-4-1