title: Pathology of Gastrointestinal Neuroendocrine Tumors: An Update.
abstract: Gastrointestinal (GI) neuroendocrine tumors (NETs) are a heterogeneous group of relatively slow-growing neoplasms with marked site-specific differences in hormonal secretion and clinical behavior. Most are sporadic neoplasms, with only 5% to 10% arising in patients with hereditary disorders, most commonly in multiple endocrine neoplasia type 1. Although a uniform terminology is not universally accepted, use of the 4-category WHO classification of these tumors is becoming more widespread, and recommendations for tumor grading and staging have been recently formulated. Most GI NETs are easily recognized on routine histologic examination; rarely, a limited panel of immunohistochemical markers may be useful in establishing the diagnosis. This article describes general and site-specific features of these tumors and outlines potential pitfalls in diagnosis.
authors.affiliation: Department of Pathology, Columbia University Medical Center, 630 West 168th Street, New York, NY 20032, USA.
authors.forename: Roger K
authors.initials: RK
authors.lastname: Moreira
authors.affiliation: Department of Pathology, Vanderbilt University Medical Center, 1161 21st Avenue South, Nashville, TN 32732, USA. Electronic address: kay.washington@vanderbilt.edu.
authors.forename: Kay
authors.initials: K
authors.lastname: Washington
keywords: Carcinoid; Gastrointestinal; Neuroendocrine