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High-grade gastroenteropancreatic neuroendocrine carcinoma

Halfdan Sorbye, MD
Jonathan R Strosberg, MD
Section Editor
Richard M Goldberg, MD
Deputy Editor
Diane MF Savarese, MD


High-grade neuroendocrine carcinomas of the gastrointestinal (GI) tract and pancreas (gastroenteropancreatic [GEP] neuroendocrine carcinomas [NECs]) are a heterogeneous group of aggressive malignancies with a high propensity for distant metastases and an ominous prognosis, even when clinically localized. The classification and nomenclature of neuroendocrine neoplasms have evolved over the last two decades. GEP neuroendocrine neoplasms are classified based upon morphology and proliferation rates as either well-differentiated (low- or intermediate-grade) neuroendocrine tumors (NETs) or poorly differentiated (high-grade) NECs (table 1) [1]. This classification system reflects the more indolent behavior of NETs compared with the far more aggressive behavior that is observed with NECs, which parallels that of poorly differentiated neuroendocrine carcinomas arising in the lung. (See "Pathology, classification, and grading of neuroendocrine tumors arising in the digestive system", section on 'Historical evolution' and "Large cell neuroendocrine carcinoma of the lung" and "Pathobiology and staging of small cell carcinoma of the lung".)

This topic review will cover the epidemiology, clinical features, diagnosis, staging, prognosis and treatment of high-grade GEP NECs. A more in-depth discussion of pathology and classification of neuroendocrine neoplasms arising in the digestive system; clinical characteristics, localization, and staging of GI tract NETs and pancreatic NETs; the presentation, prognosis, and biochemical monitoring of metastatic gastroenteropancreatic NETs; treatment options including both local therapies and systemic therapies for well-differentiated metastatic GEP NETs; other non-gastroenteropancreatic extrapulmonary sites of small cell cancer; and issues related to presentation, evaluation, and treatment of neuroendocrine neoplasms of unknown primary site are presented elsewhere:

(See "Pathology, classification, and grading of neuroendocrine tumors arising in the digestive system".)

(See "Clinical characteristics of carcinoid tumors".)

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


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