Recent developments in imaging of pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (PNETs) are very rare, accounting for 1-2% of all pancreatic neoplasms. They are classified into functioning and non-functioning and their behavior varies widely from benign to highly malignant. For their investigation, a variety of anatomical and functional imaging methods are available. Anatomical methods include computed tomography (CT), magnetic resonance imaging, and ultrasonography. Functional methods include scintigraphy and positron emission tomography (PET). A combination of anatomical and morphological methods results in the so-called hybrid imaging, such as PET/CT. We herein discuss the currently available imaging modalities for the investigation of PNETs and, more specifically, their applications in tumor detection and staging as well as in choice of therapy, imaging follow up and prediction of response, with emphasis on the recent developments.