title: Patients with sporadic duodenal adenoma are a high-risk group for advanced colorectal neoplasia: results of a case-control study.
abstract: OBJECTIVE
  To evaluate colorectal cancer risk among patients with sporadic duodenal neoplasia using a case-control protocol.
  
  
  METHODS
  Cases were 35 patients referred for the management of sporadic duodenal adenoma and who underwent colonoscopy. Colonoscopy findings among cases were compared with those from a control group matched for age and sex (two controls per case) without duodenal adenoma. Colonoscopy findings were categorized as adenoma, advanced adenoma, cancer or advanced neoplasia. The two groups were compared using the chi-squared test. Odds ratio and 95% confidence intervals were calculated.
  
  
  RESULTS
  Colorectal adenoma was present in 31% of cases vs. 24% of controls, advanced neoplasia in 29% vs. 4%, advanced adenoma in 23% vs. 3% and adenocarcinoma in 6% vs. 1%. The relative risks of advanced colorectal adenoma and advanced colorectal neoplasia in cases were 10.1 (95% CI: 1.8-100.1, P = 0.003) and 8.9 (95% CI: 2.1-53.3, P = 0.001), respectively.
  
  
  CONCLUSIONS
  The relative risk of advanced colorectal adenoma and advanced neoplasia in cases was nine- to 10-fold that among controls. Patients with sporadic duodenal adenoma represent a high-risk group for advanced colorectal neoplasia and should therefore undergo complete colonoscopy.
authors.affiliation: Service des Maladies de l'Appareil Digestif, hôpital Pontchaillou, Rennes, France.
authors.forename: P
authors.initials: P
authors.lastname: Pequin
authors.forename: S
authors.initials: S
authors.lastname: Manfredi
authors.forename: V
authors.initials: V
authors.lastname: Quentin
authors.forename: D
authors.initials: D
authors.lastname: Heresbach
authors.forename: J
authors.initials: J
authors.lastname: Boyer
authors.forename: L
authors.initials: L
authors.lastname: Siproudhis
authors.forename: J-F
authors.initials: JF
authors.lastname: Bretagne
mesh_terms: D000236:Adenoma / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D004379:Duodenal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011230:Precancerous Conditions / Q000473:pathology*; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors