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Classification, epidemiology, clinical presentation, localization, and staging of pancreatic neuroendocrine tumors (islet-cell tumors)

Jonathan R Strosberg, MD
Section Editors
David M Nathan, MD
David C Whitcomb, MD, PhD
Richard M Goldberg, MD
Deputy Editors
Diane MF Savarese, MD
Shilpa Grover, MD, MPH


Pancreatic neuroendocrine tumors (pancreatic NETs), also known as islet cell tumors, are rare neoplasms that arise in the endocrine tissues of the pancreas (picture 1). They can secrete a variety of peptide hormones, including insulin, gastrin, glucagon, and vasoactive intestinal peptide (VIP), resulting in myriad clinical syndromes. In modern clinical series, however, between 50 and 75 percent of pancreatic NETs are nonfunctioning (ie, unassociated with a hormonal syndrome).

This topic review will cover the classification, clinical presentation, localization and staging of well-differentiated pancreatic NETs. A discussion of surgical management of sporadic pancreatic NETs, clinical features, diagnostic evaluation and treatment of high-grade gastroenteropancreatic neuroendocrine carcinomas, and specific topics that address the presentation and management of functioning pancreatic NETs and neuroendocrine neoplasms of unknown primary site are all presented elsewhere.

(See "Surgical resection of sporadic pancreatic neuroendocrine tumors".)

(See "High-grade gastroenteropancreatic neuroendocrine carcinoma".)

(See "Insulinoma".)


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Literature review current through: Sep 2016. | This topic last updated: Aug 15, 2016.
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