title: Utilization and yield of surveillance colonoscopy in the continued follow-up study of the polyp prevention trial.
abstract: OBJECTIVE
  Prospective information on the use and yield of surveillance colonoscopy is limited. We examined the use and yield of surveillance colonoscopy among participants in the Polyp Prevention Trial (PPT) after the 4-year dietary intervention trial ended.
  
  
  METHODS
  We followed a cohort of 1297 participants. We calculated the cumulative probability of posttrial colonoscopy and investigated the yield and predictive factors for adenoma and advanced adenoma recurrence over a mean time of 5.9 years.
  
  
  RESULTS
  Seven-hundred seventy-four subjects (59.7%) had a repeat colonoscopy. Among 431 subjects with low-risk adenomas (1-2 nonadvanced adenomas) at baseline and no adenoma recurrence at the end of the PPT (lowest-risk category), 30.3% underwent a repeat colonoscopy within 4 years. Among 55 subjects who had high-risk adenomas (advanced adenoma and/or > or =3 nonadvanced adenomas) at baseline and again at the final PPT colonoscopy (highest-risk category), 41.3% had a colonoscopy within 3 years and 63.5% had an examination within 5 years. The cumulative yield of advanced adenoma through 6 years was 3.6% for the lowest-risk category, 38.9% for the highest-risk category, and ranged from 6.6% to 13.8% for intermediate-risk categories. An advanced adenoma at the final PPT colonoscopy was associated significantly with an advanced adenoma recurrence during surveillance (hazard ratio, 6.2; 95% confidence interval, 2.5-15.4).
  
  
  CONCLUSIONS
  Surveillance colonoscopy was overused for low-risk subjects and underused for high-risk subjects. Advanced adenoma yield corresponded with the adenoma risk category. Resource consumption can be better managed by aligning use with the risk of adenoma recurrence.
authors.affiliation: Cancer Prevention Fellowship Program, Office of Preventive Oncology, National Cancer Institute, Bethesda, Maryland 20892, USA. laiyemoa@mail.nih.gov
authors.forename: Adeyinka O
authors.initials: AO
authors.lastname: Laiyemo
authors.forename: Paul F
authors.initials: PF
authors.lastname: Pinsky
authors.forename: Pamela M
authors.initials: PM
authors.lastname: Marcus
authors.forename: Elaine
authors.initials: E
authors.lastname: Lanza
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Cross
authors.forename: Arthur
authors.initials: A
authors.lastname: Schatzkin
authors.forename: Robert E
authors.initials: RE
authors.lastname: Schoen
mesh_terms: D000236:Adenoma / Q000175:diagnosis* / Q000473:pathology / Q000517:prevention & control*; D000368:Aged; D015331:Cohort Studies; D003111:Colonic Polyps / Q000175:diagnosis* / Q000473:pathology / Q000517:prevention & control*; D003113:Colonoscopy / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000706:statistics & numerical data*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis; D015995:Prevalence; D012720:Severity of Illness Index