title: Unusual tumors of the appendix and pseudomyxoma peritonei.
abstract: This report covers hyperplastic and neoplastic lesions of the human vermiform appendix that, although unusual, are likely to be encountered by general surgical pathologists. Topics include epithelial neoplasms, hyperplastic polyps, diffuse epithelial hyperplasia, pseudomyxoma peritonei, goblet cell and tubular carcinoid tumors, neuroma, and neurogenous hyperplasia. We discuss recent advances in the prognosis and management of appendiceal carcinoma, current controversies regarding the relationship between ovarian and appendiceal epithelial neoplasms, the concept of the mucinous tumor of uncertain malignant potential (UMP), and practical aspects of reporting pseudomyxoma peritonei. Classical carcinoid tumors are beyond the scope of this article, and primary neoplasms that are so rare they occur in the literature only as isolated case reports are not covered.
authors.affiliation: Department of Hepatic and Gastrointestinal Pathology, Armed Forces Institute of Pathology, Washington, DC, USA.
authors.forename: N J
authors.initials: NJ
authors.lastname: Carr
authors.forename: L H
authors.initials: LH
authors.lastname: Sobin
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology; D000236:Adenoma / Q000473:pathology; D001063:Appendiceal Neoplasms / Q000175:diagnosis* / Q000473:pathology* / Q000628:therapy; D002276:Carcinoid Tumor / Q000473:pathology; D006801:Humans; D010534:Peritoneal Neoplasms / Q000175:diagnosis* / Q000473:pathology* / Q000628:therapy; D011127:Polyps / Q000473:pathology; D011230:Precancerous Conditions / Q000473:pathology; D011379:Prognosis; D011553:Pseudomyxoma Peritonei / Q000175:diagnosis* / Q000473:pathology* / Q000628:therapy