title: Risk stratification for advanced proximal colon neoplasm and individualized endoscopic screening for colorectal cancer by a risk-scoring model.
abstract: BACKGROUND
  Only 30% to 40% of patients with advanced proximal neoplasms (APN) have distal colon neoplasms.
  
  
  OBJECTIVE
  To develop a risk score model for APN and propose an individualized screening protocol for colorectal cancer.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Tertiary-care center.
  
  
  METHODS
  Derivation cohort (6200 adults) and validation cohort (1389 adults).
  
  
  METHODS
  Screening colonoscopy.
  
  
  METHODS
  An APN risk score model was developed from the derivation cohort (6200 adults) and was tested in the validation cohort (1389 adults), who underwent screening colonoscopy.
  
  
  RESULTS
  Age, male sex, and smoking were clinical risk factors for APN. The presence of a distal neoplasm was a sigmoidoscopic risk factor for APN. We calculated APN risk scores (0-8) based on these variables and classified patients as low risk (0-2) or high risk (3-8). In the validation cohort, the relative risk of APN was 3.5-fold higher in the high-risk group than in the low-risk group. Our model suggests that colonoscopy should be performed as an initial screening test in patients with a high clinical risk for APN. Sigmoidoscopy should be performed initially in patients with low clinical risk for APN followed by supplementary colonoscopy in those with high APN risk scores based on both clinical and sigmoidoscopic risk factors. This protocol detected APN in 22 of 34 APN+ patients (64.7%) with little increase in the endoscopy burden, whereas only 16 of 34 APN+ patients (47.1%) would be identified by initial sigmoidoscopy followed by colonoscopy only in cases with distal neoplasms.
  
  
  CONCLUSIONS
  Retrospective design.
  
  
  CONCLUSIONS
  Our APN risk score model provides an algorithm for efficient screening of colorectal cancer by sigmoidoscopy and colonoscopy.
authors.affiliation: Health Promotion Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Hye Won
authors.initials: HW
authors.lastname: Park
authors.forename: Seungbong
authors.initials: S
authors.lastname: Han
authors.forename: Jong-Soo
authors.initials: JS
authors.lastname: Lee
authors.forename: Hye-Sook
authors.initials: HS
authors.lastname: Chang
authors.forename: Don
authors.initials: D
authors.lastname: Lee
authors.forename: Jae-Won
authors.initials: JW
authors.lastname: Choe
authors.forename: Seung-Jae
authors.initials: SJ
authors.lastname: Myung
authors.forename: Suk-Kyun
authors.initials: SK
authors.lastname: Yang
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Kim
authors.forename: Jeong-Sik
authors.initials: JS
authors.lastname: Byeon
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D002985:Clinical Protocols; D015331:Cohort Studies; D044682:Colon, Ascending / Q000473:pathology*; D044684:Colon, Transverse / Q000473:pathology*; D003110:Colonic Neoplasms / Q000175:diagnosis* / Q000209:etiology; D003113:Colonoscopy; D003661:Decision Support Techniques; D055088:Early Detection of Cancer / Q000379:methods*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012812:Sigmoidoscopy