Article Text

other Versions

PDF
Serrated lesions in colorectal cancer screening: detection, resection, pathology and surveillance
  1. James E East1,
  2. Michael Vieth2,
  3. Douglas K Rex3
  1. 1Translational Gastroenterology Unit, University of Oxford, Oxford, UK
  2. 2Institute of Pathology, Klinikum Bayreuth, Bayreuth, Germany
  3. 3Indiana University School of Medicine, Indianapolis, Indiana, USA
  1. Correspondence to Dr Douglas K Rex, Indiana University Hospital UH 4100, 550 North University Blvd, Indianapolis, IN 46202, USA; drex{at}iupui.edu

Statistics from Altmetric.com

Key messages

  • Colorectal cancer can occur via more than one molecular pathway. The serrated pathway probably accounts for 20%–30% of colorectal cancer.

  • Histopathological nomenclature for serrated lesions varies internationally. We suggest the terms hyperplastic polyp (HP), sessile serrated polyp (SSP), and traditional serrated adenoma to describe these lesions.

  • Colonoscopy is the best detection tool for serrated polyps, but detection rates are variable.

  • Chromoendoscopy and slower withdrawal time are the only interventions that have been demonstrated to increase serrated lesion detection. High-definition endoscopy and right colon retroflexion may have a role.

  • All polyps proximal to the recto-sigmoid junction should be removed. A benchmark rate of 4.5% for detection of proximal serrated lesions (HPs plus SSPs proximal to splenic flexure) in screening has been suggested for US-based colonoscopic screening, but implementing a target for serrated lesions in clinical practice is currently impractical.

  • DNA-based detection significantly augments serrated lesion detection in stool-based screening programmes.

  • There are limited data to guide surveillance after resection of serrated lesions; however, the logic behind surveillance for serrated lesions is consistent with that for conventional adenomas.

Introduction

A strong evidence base supports colorectal cancer screening. Interruption of the adenoma-carcinoma sequence by endoscopic polypectomy has been considered the key step in preventing the development of colorectal cancer.1 Higher adenoma detection rates (ADR) at colonoscopy have a linear correlation with lower postcolonoscopy colorectal cancer (PCCRC) rates and death from PCCRC.2 However, colonoscopy is not as effective in prevention of colorectal cancer in the right colon as in the left.3–5 Interval cancers are often right-sided and hypermethylated, not consistent with an origin in conventional adenomas.4 Recent molecular approaches to colorectal cancer indicate there are three or more distinct molecular pathways to colorectal cancer, including a pathway arising through serrated lesions.6 ,7

Serrated lesions pose multiple challenges in clinical …

View Full Text

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.