Predicting aggressive behavior in the group of nonfunctional pancreatic neuroendocrine tumors (NF P-NET) remains a difficult problem in clinical practice. At present, the treatment planning in P-NET is significantly restricted by the limited results of conventional imaging. In addition, increasing use of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) is increasing the number of NF P-NETs detected. Somatostatin receptor scintigraphy (SRS) combined with anatomical imaging are the conventional modalities in imaging of P-NET, but by these methods the diagnostic accuracy still remains compromised. Furthermore, recently encouraging results have been obtained in P-NET using 68Ga-labelled somatostatin analog, DOTA-1-NaI3-octreotide (68Ga-DOTANOC) positron emission tomography-computed tomography (PET-CT).

The aim of the current project is to evaluate the possibility to enhance the diagnostic accuracy by using dual trace functional imaging 18F-labelled fluorodeoxyglucose (18F-FDG) and 68Ga-DOTANOC PET-CT imaging in patients with NF P-NET. The study consists of 20 patients with NF P-NET. The patients enrolled in the study will be imaged 68Ga-DOTANOC and 18F-FDG PET-CT followed by surgery or follow-up with endoscopic ultrasonography (EUS) biopsies. The data will be collected between autumn 2015 and spring 2018.

Inclusion Criteria:

• suspicion of nonfunctional P-NET on primary CT (i.e hypervascularity) or MRI
• signed informed consent

Exclusion Criteria:

• vulnerable study subjects such as described in Finnish law concerning clinical studies (disabled, children, pregnant or breast-feeding women, prisoners) will not be included.