title: Sporadic duodenal adenoma is associated with colorectal neoplasia.
abstract: OBJECTIVE
  The objective of this study was to assess the association between colorectal neoplasia and sporadic duodenal adenoma.
  
  
  METHODS
  A retrospective case control study was conducted using the databases of two major teaching hospitals in Western Australia. The frequency of colorectal neoplasia in patients with sporadic duodenal adenomas was compared with that in a control group of patients presenting for endoscopies. The frequency of colorectal cancer in duodenal adenoma patients was also compared with the population incidence.
  
  
  RESULTS
  Of 56 sporadic duodenal adenoma patients, 34 (61%) had been colonoscoped. When comparing the findings between patients with sporadic duodenal adenoma and an endoscoped control group, all colorectal neoplasias were significantly more common in the duodenal adenoma group (56% v 33%; odds ratio (OR) 2.4 (95% confidence intervals (CI) 1.1-5.4)). Although finding either advanced colorectal adenoma or cancer was also more common in duodenal adenoma patients (38% v 19%; OR 2.3 (95% CI 1.0-5.2)), as was finding colorectal cancer alone (21% v 8%; OR 3.0 (95% CI 1.0-9.1)), the results were not statistically significant. However, the incidence of colorectal cancer was much greater in duodenal adenoma patients than in the population (p<0.001).
  
  
  CONCLUSIONS
  Sporadic duodenal adenoma has a clinically important association with colorectal neoplasia. Thus patients with duodenal adenomas should undergo colonoscopy to detect colorectal neoplasia.
authors.affiliation: Department of Gastroenterology and Hepatology, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia.
authors.forename: M A
authors.initials: MA
authors.lastname: Murray
authors.forename: M J
authors.initials: MJ
authors.lastname: Zimmerman
authors.forename: H C
authors.initials: HC
authors.lastname: Ee
mesh_terms: D000236:Adenoma / Q000150:complications*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000150:complications*; D004379:Duodenal Neoplasms / Q000150:complications*; D016099:Endoscopy, Gastrointestinal; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012189:Retrospective Studies; D012306:Risk