title: Colonoscopy surveillance: guidelines for polyps and IBD.
abstract: BACKGROUND
  Evidence on the optimal postpolypectomy surveillance strategies for subjects undergoing colorectal cancer screening as well as among IBD patients, is limited. In the absence of strong evidence, currently adopted guidelines are mainly based on experts' opinion and low quality data and they are often influenced by a safety-first approach and are not consistent. Given the lack of conclusive data from randomized controlled trials and uncertainty about the extent of risk of adenoma patients developing CRC in the future, there is uncertainty regarding cost-effectiveness of surveillance protocols. This may partly explain discrepancies in guidelines recommendations, with regard to definition of risk categories and of the recommended surveillance intervals. Uncertainty persists concerning management of patients with small advanced adenomas (size <10 mm and villous component >20% and/or high-grade dysplasia), high-risk adenomas and serrated polyps.
  
  
  METHODS
  We retrieved the most recent guidelines for postpolypectomy surveillance from Europe and US and we conducted an additional PUBMED search for guidelines, systematic reviews (SR) and primary studies published after the last search update of the most recent review,8 presenting data about predictors of the risk of CRC and adenoma recurrence following polypectomy, and also about surveillance practice and surveillance related workload
  
  
  RESULTS
  The findings of surveys conducted in clinical settings and population screening programs are showing a wide variability in the recommended surveillance protocols.
  
  
  CONCLUSIONS
  To be able to adopt evidence bases approach additional information is needed about the risk of CRC and/or advanced adenomas with and without surveillance, as well as about the efficacy of endoscopic surveillance in reducing CRC risk. Indeed, the offer of colonoscopy for surveillance may not be justified if the risk of developing CRC among subjects with removed adenomas is not significantly increased compared to the general population, or, even if the risk is increased, performance of surveillance exams does not result in a reduction of this risk.
authors.affiliation: Città della Salute e della Scienza University Hospital, SCDO Epidemiology, Screening, Cancer Registry, CPO, Turin, Italy - carlo.senore@cpo.it.
authors.forename: Carlo
authors.initials: C
authors.lastname: Senore
authors.forename: Roberto
authors.initials: R
authors.lastname: Lorenzetti
authors.forename: Cristina
authors.initials: C
authors.lastname: Bellisario
authors.forename: Cesare
authors.initials: C
authors.lastname: Hassan
mesh_terms: D000236:Adenoma / Q000601:surgery; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000517:prevention & control* / Q000601:surgery; D055088:Early Detection of Cancer; D006801:Humans; D011159:Population Surveillance; D017410:Practice Guidelines as Topic