Shih-Hsin Chen1, Yu-Chuan Chang2, Tsann-Long Hwang3, Jen-Shi Chen4, Wen-Chi Chou4, Chia-Hsun Hsieh4, Ta-Sen Yeh3, Jun-Te Hsu3, Chun-Nan Yeh3, Jeng-Hwei Tseng5, Tse-Ching Chen6, Tzu-Chen Yen7. 1. Department of Nuclear Medicine and Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan. 2. Department of Nuclear Medicine and Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan; Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan. 3. Department of Surgery, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan. 4. Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan. 5. Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan. 6. Department of Pathology, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan. 7. Department of Nuclear Medicine and Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan. Electronic address: yen1110@cgmh.org.tw.
Abstract
BACKGROUND/ PURPOSE: To investigate the diagnostic accuracy of 68Ga-DOTATOC and 18F-FDG PET/CT to identify the primary foci in Taiwanese patients with clinically suspected neuroendocrine tumors (NET) and NET of unknown primary site. METHODS: Patients with clinically suspected NET and NET of unknown primary site were eligible. All participants underwent a conventional workup (including CT, MR, endoscopic ultrasound), 68Ga-DOTATOC, and 18F-FDG PET/CT. The results of pathology and findings on clinical follow-up served as the gold standard. RESULTS: Among the 36 patients included in the study, we were able to identify the primary tumor in 17 participants (47.2%). The overall sensitivity values of 68Ga-DOTATOC, 18F-FDG, and conventional workup were 88%, 41%, and 53%, respectively, whereas the specificities were 100%, 100%, 68%, respectively. The areas under curve of 68Ga-DOTATOC, 18F-FDG, and conventional workup were 0.941, 0.706, and 0.607, respectively. 68Ga-DOTATOC was more sensitive than 18F-FDG and more specific than conventional workup. Treatment changes as a result of 68Ga-DOTATOC PET/CT findings occurred in 12 (33.3%) of the 36 study participants. CONCLUSION: Our data confirm the usefulness of 68Ga-DOTATOC in the identification of NET. In addition, treatment modifications as a result of 68Ga-DOTATOC PET/CT findings were evident in approximately one third of NET patients.
BACKGROUND/ PURPOSE: To investigate the diagnostic accuracy of 68Ga-DOTATOC and 18F-FDG PET/CT to identify the primary foci in Taiwanese patients with clinically suspected neuroendocrine tumors (NET) and NET of unknown primary site. METHODS:Patients with clinically suspected NET and NET of unknown primary site were eligible. All participants underwent a conventional workup (including CT, MR, endoscopic ultrasound), 68Ga-DOTATOC, and 18F-FDG PET/CT. The results of pathology and findings on clinical follow-up served as the gold standard. RESULTS: Among the 36 patients included in the study, we were able to identify the primary tumor in 17 participants (47.2%). The overall sensitivity values of 68Ga-DOTATOC, 18F-FDG, and conventional workup were 88%, 41%, and 53%, respectively, whereas the specificities were 100%, 100%, 68%, respectively. The areas under curve of 68Ga-DOTATOC, 18F-FDG, and conventional workup were 0.941, 0.706, and 0.607, respectively. 68Ga-DOTATOC was more sensitive than 18F-FDG and more specific than conventional workup. Treatment changes as a result of 68Ga-DOTATOC PET/CT findings occurred in 12 (33.3%) of the 36 study participants. CONCLUSION: Our data confirm the usefulness of 68Ga-DOTATOC in the identification of NET. In addition, treatment modifications as a result of 68Ga-DOTATOC PET/CT findings were evident in approximately one third of NET patients.