title: Do surveillance intervals in patients with more than five adenomas at index colonoscopy be shorter than those in patients with three to four adenomas? A Korean Association for the Study of Intestinal Disease study.
abstract: OBJECTIVE
  There is controversy about the surveillance interval after colonoscopy when 5-10 adenomas have been found on index colonoscopy. This study aimed to investigate the risk of colorectal neoplasm (CRN) according to the number of adenomas at index colonoscopy.
  
  
  METHODS
  A retrospective, multicenter study was conducted at 10 university hospitals in Korea. We included 1394 patients with ≥ 3 adenomas at index colonoscopy. The risk of advanced CRN was compared according to the number of adenomas (intermediate risk group, 3-4 small adenomas or at least one ≥ 10 mm, and high risk group, ≥ 5 small adenomas or ≥ 3 at least one ≥ 10 mm).
  
  
  RESULTS
  Overall, 164 (11.8%) developed an advanced CRN after a mean of 4.0 years from baseline colonoscopy. The 3-year and 5-year risk of advanced CRN was 2.1% (95% CI 2.09-2.11) and 14.4% (95% CI 14.36-14.44) in intermediate risk group and 3.2% (95% CI 3.19-3.21) and 23.3% (95% CI 19.15-19.25) in high risk group (P = 0.01). Having ≥ 5 adenomas (OR = 1.57, 95% CI 1.11-2.23, P = 0.01) detected at index colonoscopy was a significant risk factor for developing advanced CRN.
  
  
  CONCLUSIONS
  Although risk of advanced CRN in patients with 5-10 adenomas was significantly higher than that in patients with 3-4 adenomas, the cumulative risk at 3 years was low at 3.2%. Thus, we suggest that a 3-year surveillance interval might be appropriate for the patients with 5-10 adenomas, and further prospective studies are needed to investigate whether more intensive surveillance is needed in this group.
authors.affiliation: Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Soo-Kyung
authors.initials: SK
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Young Seok
authors.initials: YS
authors.lastname: Song
authors.affiliation: Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Yoon Suk
authors.initials: YS
authors.lastname: Jung
authors.affiliation: Digestive Disease Center, CHA Bundang Medical Center, CHA University, Seongnam, Korea.
authors.forename: Won Hee
authors.initials: WH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Guri, Korea.
authors.forename: Chang
authors.initials: C
authors.lastname: Soo Eun
authors.affiliation: Department of Internal Medicine, Digestive Disease Center and Research institute, Soonchunhyang University School of Medicine, Bucheon, Korea.
authors.forename: Bong Min
authors.initials: BM
authors.lastname: Ko
authors.affiliation: Department of Internal Medicine, Digestive Disease Research Institute, Wonkwang University College of Medicine, Iksan, Korea.
authors.forename: Geom Seog
authors.initials: GS
authors.lastname: Seo
authors.affiliation: Department of Internal Medicine, Kyung Hee University Hospital at Gang Dong, Kyung Hee University School of Medicine, Seoul, Korea.
authors.forename: Jae Myung
authors.initials: JM
authors.lastname: Cha
authors.affiliation: Department of Internal Medicine, Division of Gastroenterology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jae Jun
authors.initials: JJ
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, School of Medicine, Ewha Womans University, Seoul, Korea.
authors.forename: Chang
authors.initials: C
authors.lastname: Mo Moon
authors.affiliation: Department of Medicine, Division of Gastroenterology, Soonchunhyang University College of Medicine, Cheonan, Korea.
authors.forename: Yunho
authors.initials: Y
authors.lastname: Jung
authors.affiliation: Institute for Digestive Research, Digestive Disease Center, Soonchunhyang University College of Medicine, Seoul, Korea.
authors.forename: Seong Ran
authors.initials: SR
authors.lastname: Jeon
authors.affiliation: Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Dong Il
authors.initials: DI
authors.lastname: Park
mesh_terms: D000236:Adenoma / Q000175:diagnosis* / Q000453:epidemiology* / Q000517:prevention & control; D000368:Aged; D003113:Colonoscopy / Q000706:statistics & numerical data*; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000517:prevention & control; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012306:Risk; D012307:Risk Factors; D013997:Time Factors
keywords: adenoma; colorectal; surveillance