Multimodal imaging with ^sup 18^F-FDG-PET/CT and ^sup 111^In-Octreotide SPECT in patients with metastatic medullary thyroid carcinoma

• Published in: Annals of nuclear medicine Vol. 30; no. 3; p. 234
• Main Authors: De Luca, Serena, Fonti, Rosa, Camera, Luigi, Salvatore, Barbara, Faggiano, Antongiulio, Ciarmiello, Andrea, Segreto, Sabrina, Colao, Annamaria, Salvatore, Marco, Del Vecchio, Silvana
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Nature B.V 01-04-2016
• ISSN: 0914-7187; 1864-6433
• DOI: 10.1007/s12149-015-1056-5

Objective The aim of our study was to determine the role of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (^sup 18^F-FDG-PET/CT) and indium-111 Octreotide single photon emission tomography (^sup 111^In-Octreotide SPECT) in the evaluation of metastatic medullary thyroid carcinoma (MMTC). Methods Twenty-five MMTC patients were retrospectively evaluated. All patients had undergone whole-body ^sup 18^F-FDG-PET/CT including 20 who had also undergone ^sup 111^In-Octreotide SPECT within a maximum interval of 6 weeks. Diagnostic contrast-enhanced computed tomography (CT) alone or as part of ^sup 18^F-FDG-PET/CT examination was performed in all patients. Results Contrast-enhanced CT detected a total of 131 lesions including 79 enlarged lymph nodes and 14 bone lesions. ^sup 18^F-FDG-PET/CT visualized a total of 92 true positive lesions (SUV^sub max^ range 1.1-10.0, mean 4.0 ± 1.7) including 66 lymph nodes, 7 of which were not enlarged on CT, and 8 bone metastases. In the 20 patients studied with both techniques, a total of 64 and 46 true positive lesions were detected by ^sup 18^F-FDG-PET/CT and ^sup 111^In-Octreotide SPECT, respectively. In particular, ^sup 18^F-FDG uptake was found in 43 lymph nodes and in 7 bone metastases whereas ^sup 111^In-Octreotide uptake was detected in 27 lymph nodes and in 10 bone metastases. Conclusions In MMTC patients, ^sup 18^F-FDG-PET/CT provides a useful contribution mainly in evaluating lymph node involvement whereas ^sup 111^In-Octreotide SPECT can contribute to the detection and somatostatin receptor characterization especially of bone lesions.