Bell, DianaHanna, Ehab Y.Weber, Randal S.DeMonte, FrancoTriantafyllou, AsteriosLewis, James S., Jr.Cardesa, AntonioSlootweg, Pieter J.Stenman, GoranGnepp, Douglas R.Devaney, Kenneth O.Rodrigo, Juan P.Rinaldo, AlessandraWenig, Bruce M.Westra, William H.Bishop, Justin A.Hellquist, HenrikHunt, Jennifer L.Kusafuka, KimihidePerez-Ordonez, BayardoWilliams, Michelle D.Takes, Robert P.Ferlito, Alfio2017-04-072017-04-072016-041043-3074http://hdl.handle.net/10400.1/9537Neuroendocrine neoplasms of the sinonasal region, which are relatively uncommon but clinically very important, are reviewed here in the light of current knowledge. Using a definition for neuroendocrine based on phenotypic, histologic, immunohistochemical, and electron microscopic features rather than histogenetic criteria, sinonasal neuroendocrine carcinomas are examined with a particular emphasis on the small-cell and large-cell subtypes. This is followed by revisiting olfactory neuroblastoma because it is also a tumor that shows a neuroendocrine phenotype. Kadish clinical and Hyams histologic grading systems as prognosticators of olfactory neuroblastoma are also considered in detail. Finally, controversies regarding sinonasal undifferentiated carcinoma as a neuroendocrine tumor are discussed and a possible relationship with high-grade olfactory neuroblastoma is explored. Genetic events and current management of these tumors are also outlined. (C) 2015 Wiley Periodicals, Inc.engjournal article10.1002/hed.24152