The epidemiology of pancreatic neuroendocrine neoplasms (PNENs) in Asia has been clarified through epidemiologicalstudies, including one conducted in Japan, and subsequently another in South Korea. As endoscopic ultrasonography(EUS) has become more widely accessible, endoscopic ultrasound-fine needle aspiration (EUS-FNA) has been performedin pancreatic tumors for which the clinical course was only monitored previously. This has enabled accurate diagnosisof pancreatic tumors based on the 2010 WHO classification; as a result, the number of patients with an accurate diagnosishas increased. Although surgery has been the standard therapy for PNENs, new treatment options have becomeavailable in Japan for the treatment of advanced or inoperable PNENs; of particular note is the recent introductionof molecular target drugs (such as everolimus and sunitinib) and streptozocin. Treatment for progressive PNENs needsto be selected for each patient with consideration of the performance status, degree of tumor differentiation, tumor mass,and proliferation rate. Somatostatin receptor (SSTR)-2 is expressed in many patients with neuroendocrine tumor. Somatostatinreceptor scintigraphy (SRS), which can visualize SSTR-2 expression, has been approved in Japan. The SRSwill be a useful diagnostic tool for locating neuroendocrine neoplasms, detecting distant metastasis, and evaluatingtherapy outcomes. In this manuscript, we review the latest diagnostic methods and treatments for PNENs.

Keywords: Pancreatic endocrine tumor, Neuroendocrine neoplasm, WHO classification, Molecular target drug