Gallium-68-DOTA-NOC PET/CT of Patients With Gastroenteropancreatic Neuroendocrine Tumors: A Prospective Single-Center Study

OBJECTIVE. The objective of this study was to evaluate the role of Ga-68-labeled [1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid]-1-NaI3-octreotide (DOTA-NOC) PET/CT in the diagnosis and management of gastroenteropancreatic neuroendocrine tumors (NETs). SUBJECTS AND METHODS. One hundred nine patients (median age, 50 years) with gastroenteropancreatic NETs underwent Ga-68-DOTA-NOC PET/CT. PET/CT was performed after injection of 132-222 MBq (4-6 mCi) of Ga-68-DOTA-NOC. Images were evaluated by two experienced nuclear medicine physicians both qualitatively as well as quantitatively (maximum standardized uptake value [SUVmax]). Results of PET/CT were compared with the results of conventional imaging. Histopathology results, when available, and follow-up PET/CT or conventional imaging with biochemical markers were considered to be the reference standards. RESULTS. Gallium-68-DOTA-NOC PET/CT showed sensitivity and specificity of 78.3% and 92.5%, respectively, for primary tumor and 97.4% and 100% for metastases. It was better than a conventional imaging modality for the detection of both primary tumor (p < 0.001) and metastases (p < 0.0001). It changed the management strategy in 21 patients (19%) and supported management decisions in 32 patients (29%). CONCLUSION. Gallium-68-DOTA-NOC PET/CT appears to be a highly sensitive and specific modality for the detection of gastroenteropancreatic NET. It is better than conventional imaging for the evaluation of gastroenteropancreatic NETs and can have a significant impact on patient management.