title: Risk of developing advanced colorectal neoplasia after removing high-risk adenoma detected at index colonoscopy in young patients: A KASID study.
abstract: OBJECTIVE
  Advanced adenoma (> 10 mm in diameter, villous structure, or high-grade dysplasia) in young patients may have different characteristics and prognosis compared with those in older patients. We aimed to compare the incidence of colorectal neoplasms in young patients with older patients after removing high-risk adenoma (advance adenoma or ≥ 3 adenomas).
  
  
  METHODS
  A retrospective, multicenter study was conducted at 13 university hospitals in Korea. The 1479 patients who removed high-risk adenoma at index colonoscopy and followed by surveillance colonoscopy ≥ 2.5 years after were included. The cumulative incidence of overall and advanced colorectal neoplasms was compared according to the age groups (group 1: < 50 years, group 2: 50-70 years, and group 3: ≥ 70 years).
  
  
  RESULTS
  The prevalence of advance adenoma detected at index colonoscopy was significantly higher in group 1 than in groups 2 and 3 (85.4%, 78.1%, and 77.2%, respectively; P = 0.035). The 5 years cumulative incidence of overall and advanced colorectal neoplasms were 61.9%, 67.9%, and 74.7% (P < 0.001), and 11.7%, 17.9%, and 27.1% (P = 0.001) in groups 1, 2, and 3, respectively. In multivariate analysis, age > 70 years was a significant risk factor for developing overall (hazard ratio [HR] 1.41, 95% confidence interval [CI] 1.12-1.82, P = 0.004) and advanced colorectal neoplasms (HR = 2.56, 95% CI 1.43-4.59, P = 0.002).
  
  
  CONCLUSIONS
  The cumulative incidence of overall and advanced colorectal neoplasms was significantly higher in older patients than in young patient groups. Age was a significant risk factor for developing colorectal neoplasms after removing high-risk adenoma.
authors.affiliation: Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine.
authors.forename: Soo-Kyung
authors.initials: SK
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine.
authors.forename: Nam Hee
authors.initials: NH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine.
authors.forename: Yoon Suk
authors.initials: YS
authors.lastname: Jung
authors.affiliation: Digestive Disease Center, CHA Bundang Medical Center, CHA University, Seongnam.
authors.forename: Won Hee
authors.initials: WH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Guri.
authors.forename: Chang Soo
authors.initials: CS
authors.lastname: Eun
authors.affiliation: Digestive Disease Center and Research Institute, Department of Internal Medicine, Soonchunhyang University School of Medicine, Bucheon.
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.
authors.forename: Geom Seog
authors.initials: GS
authors.lastname: Seo
authors.affiliation: Department of Internal Medicine, Kyung Hee University Hospital at Gang Dong.
authors.forename: Jae Myung
authors.initials: JM
authors.lastname: Cha
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine.
authors.forename: Jae Jun
authors.initials: JJ
authors.lastname: Park
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Internal Medicine, Yeungnam University College of Medicine.
authors.forename: Kyeong Ok
authors.initials: KO
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, School of Medicine, Ewha Womans University.
authors.forename: Chang Mo
authors.initials: CM
authors.lastname: Moon
authors.affiliation: Department of Medicine, Division of Gastroenterology, Soonchunhyang University College of Medicine, Cheonan, Korea.
authors.forename: Yoonho
authors.initials: Y
authors.lastname: Jung
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Keimyung University School of Medicine, Daegu.
authors.forename: Eun Soo
authors.initials: ES
authors.lastname: Kim
authors.affiliation: Institute for Digestive Research, Digestive Disease Center, Soonchunhyang University College of Medicine, Seoul.
authors.forename: Seong Ran
authors.initials: SR
authors.lastname: Jeon
authors.affiliation: Department of Internal Medicine, Kyung Hee University School of Medicine.
authors.forename: Chang Kyun
authors.initials: CK
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine.
authors.forename: Dong Il
authors.initials: DI
authors.lastname: Park
mesh_terms: D000236:Adenoma / Q000453:epidemiology / Q000601:surgery*; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D003113:Colonoscopy / Q000379:methods; D015179:Colorectal Neoplasms / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D015995:Prevalence; D011379:Prognosis; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012306:Risk; D012307:Risk Factors; D013995:Time
keywords: colonoscopy; colorectal neoplasms; young adult