Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 14, 2015; 21(10): 2896-2904
Published online Mar 14, 2015. doi: 10.3748/wjg.v21.i10.2896
Endoscopic and histologic characteristics of serrated lesions
Driffa Moussata, Gilles Boschetti, Marion Chauvenet, Karine Stroeymeyt, Stéphane Nancey, Françoise Berger, Thierry Lecomte, Bernard Flourié
Driffa Moussata, Gilles Boschetti, Marion Chauvenet, Karine Stroeymeyt, Stéphane Nancey, Bernard Flourié, Department of Gastroenterology, Lyon Sud Hospital, 69310 Pierre Bénite, France
Driffa Moussata, Inserm Unit CREATIS - UMR5220 - INSERM1044, Lyon University, 69100 Villeurbanne, France
Françoise Berger, Department of Pathology, Hôpital Lyon Sud, 69310 Pierre Bénite, France
Thierry Lecomte, Department of Gastroenterology, Tours Hospital, 37000 Tours, France
Author contributions: Moussata D has written the review; Boschetti G, Chauvenet M and Stroeymeyt K have contributed to conception and acquisition of data; Berger F has revised the pathologic data; Flourié B, Nancey S and Lecomte T have revised and approved the final version to be published.
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:
Correspondence to: Driffa Moussata, MD, PhD, Department of Gastroenterology, Lyon Sud Hospital, 165 chemin du Grand Revoyet, 69310 Pierre Bénite, France.
Telephone: +33-478-861290 Fax: +33-478-861063
Received: July 7, 2014
Peer-review started: July 7, 2014
First decision: August 6, 2014
Revised: August 25, 2014
Accepted: October 14, 2014
Article in press: October 15, 2014
Published online: March 14, 2015

In recent years, a second pathway for colonic carcinogenesis, distinct from the adenomatous pathway, has been explored. This is referred to as serrated pathway and includes three types of polyp, characterised by a serrated appearance of the crypts: hyperplastic polyps (HP), sessile serrated adenomas (SSA) or lesions, and traditional serrated adenomas. Each lesion has its own genetic, as well as macroscopic and microscopic morphological features. Because of their flat aspect, their detection is easier with chromoendoscopy (carmin indigo or narrow-band imaging). However, as we show in this review, the distinction between SSA and HP is quite difficult. It is now recommended to resect in one piece as it is possible the serrated polyps with a control in a delay depending on the presence or not of dysplasia. These different types of lesion are described in detail in the present review in general population, in polyposis and in inflammatory bowel diseases patients. This review highlights the need to improve characterization and understanding of this way of colorectal cancerogenesis.

Keywords: Hyperplastic polyp, Traditional serrated adenoma, Serrated polyposis, Sessile serrated adenoma, Endoscopy, Endomicroscopy, Histology

Core tip: The serrated lesions belong to a new carcinogenesis way of colorectal cancer which is important to know and detect. Even though endoscopic techniques have improved, some difficulties remain in terms of detection because of the lesions’ shape and aspect and the fact that the endoscopists have to be aware of some characteristics. However, we argue in this article that the endoscopists have to be trained so the recognition of these pre-neoplastic lesions can be improved. Furthermore, there is a necessity to communicate well with the pathologists. This article is a review of the knowledge we currently have of serrated lesions, and their endoscopic and histologic aspects which every gastroenterologist needs to know.