The Role of Combined 68Ga-DOTANOC and 18FDG PET/CT in the Management of Patients with Pancreatic Neuroendocrine Tumors

Purpose: The aim of this study was to evaluate the effect of combined Ga-68 and F-18-FDG PET/CT on treatment management for patients with pancreatic neuroendocrine tumor (PNET). Methods: Between January 2012 and April 2014, 49 consecutive patients with a cytologically and/or histologically proven diagnosis of PNET underwent combined Ga-68 and (18)FDG PET/CT on the same day. Results: The study group consisted of 21 males and 28 females with a median age of 59 years. Disease detection was achieved in 48 out of the 49 cases with Ga-68 imaging, and in 36 of the 49 cases with (18)FDG PET/CT. These results corresponded to sensitivities of 98% for Ga-68 versus 73% for (18)FDG PET/CT. Patients with NET-G1/NET-G2 had a positive Ga-68 and negative (18)FDG PET/CT in 13 cases, whereas both 68 Ga and 18 FDG PET/CT were positive in 27 cases. Patients with NEC-G3 were positive by both Ga-68 and (18)FDG PET/CT in 7 cases and positive only by (18)FDG in 1 case. Another NEC-G3 patient was only positive by Ga-68 PET/CT. The median Ki67 was 7% for Ga-68 PET/CT-positive tumors and 10% for tumors with both Ga-68 and (18)FDG PET/CT positivity (p = 0.130). Half of the patients with a prevalent uptake of (18)FDG (n = 7) had an NEC-G3 compared with 12% of patients with a prevalent uptake of Ga-68 (p = 0.012). There were no significant differences between patients with positive Ga-68 and those with positive (18)FDG with regards to treatment choice. Conclusions: The association of (18)FDG slightly increases sensitivity of Ga-68 PET/CT alone in the diagnosis of PNET. A combined dual tracer PET/CT does not influence the choice of treatment strategy. (C) 2014 S. Karger AG, Basel