Review
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jan 14, 2016; 22(2): 853-861
Published online Jan 14, 2016. doi: 10.3748/wjg.v22.i2.853
Nonampullary duodenal adenoma: Current understanding of its diagnosis, pathogenesis, and clinical management
Chul-Hyun Lim, Young-Seok Cho
Chul-Hyun Lim, Young-Seok Cho, Division of Gastroenterology, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 137-701, South Korea
Author contributions: Lim CH collected the materials and wrote the manuscript; Cho YS wrote the manuscript and supervised the publication of this review article.
Conflict-of-interest statement: Authors declare no conflict of interests for this article.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Young-Seok Cho, MD, PhD, Division of Gastroenterology, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seoul 137-701, South Korea. yscho@catholic.ac.kr
Telephone: +82-2-22586021 Fax: +82-2-22582038
Received: June 20, 2015
Peer-review started: June 25, 2015
First decision: July 20, 2015
Revised: August 10, 2015
Accepted: October 23, 2015
Article in press: October 26, 2015
Published online: January 14, 2016
Abstract

Nonampullary duodenal adenomas are relatively common in familial adenomatous polyposis (FAP), but nonampullary sporadic duodenal adenomas (SDAs) are rare. Emerging evidence shows that duodenal adenomas, regardless of their anatomic location and whether they are sporadic or FAP-related, share morphologic and molecular features with colorectal adenomas. The available data suggest that duodenal adenomas develop to duodenal adenocarcinomas via similar mechanisms. The optimal approach for management of duodenal adenomas remains to be determined. The techniques for endoscopic resection of duodenal adenoma include snare polypectomy, endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), and argon plasma coagulation ablation. EMR may facilitate removal of large duodenal polyps. Although several studies have reported cases of successful ESD for duodenal adenomas, the procedure is technically difficult to perform safely because of the anatomical properties of the duodenum. Although current clinical practice recommends endoscopic resection of all large duodenal adenomas in patients with FAP, endoscopic treatment is usually insufficient to guarantee a polyp-free duodenum. Surgery is indicated for FAP patients with severe polyposis or nonampullary SDAs or FAP-related polyps not amenable to endoscopic resection. Further studies are needed to develop newer endoscopic techniques to guide diagnostic and therapeutic decisions for future management of nonampullary duodenal adenomas.

Keywords: Duodenal adenoma, Endoscopy, Familial adenomatous polyposis, Endoscopic mucosal resection, Endoscopic submucosal dissection

Core tip: Nonampullary duodenal adenomas are thought to progress to duodenal adenocarcinomas in a stepwise manner, with accumulation of genetic mutations, including those in APC, KRAS, and p53. Recently, using magnifying endoscopy with narrow band imaging, a novel diagnostic algorithm for real-time diagnosis of nonampullary superficial duodenal epithelial tumors was developed. Endoscopic mucosal resection may facilitate removal of large duodenal polyps. Although several studies have reported cases of successful endoscopic submucosal dissection for duodenal adenomas, the procedure is technically difficult to perform safely. Further studies are needed to develop newer endoscopic techniques for the diagnosis and treatment of nonampullary duodenal adenomas.