title: Localizing colorectal cancer by colonoscopy.
abstract: OBJECTIVE
  Colonoscopic localization of colorectal carcinoma is frequently inaccurate and unreliable.
  
  
  METHODS
  Consecutive case series.
  
  
  METHODS
  Tertiary care teaching hospital.
  
  
  METHODS
  Three hundred fourteen consecutive patients undergoing surgical resection for colorectal cancer from January 1, 2000, to December 31, 2003.
  
  
  METHODS
  Surgical resection for colorectal cancer.
  
  
  METHODS
  Incidence of erroneous site localization.
  
  
  RESULTS
  Two hundred thirty-six patients had complete endoscopic, pathologic, and operative records. Colonoscopy was inaccurate for tumor localization in 49 cases (21%). In 27 (11%) of these cases, a different procedure was required than initially planned; in an additional 10 cases (4%), the surgical approach required modification. Inaccurate localization was associated with previous colorectal procedures on both univariate analysis (odds ratio, 3.94; 95% confidence interval, 1.50-10.32; P<.005) and multivariate analysis (odds ratio, 4.47; 95% confidence interval, 1.64-12.08; P = .003). Having the colonoscopy performed by a surgeon trended toward protection from error on multivariate analysis (odds ratio, 0.47; 95% confidence interval, 0.20-1.08; P = .07). Age, sex, diverticular disease, endoscopist volume and years of training, and bowel preparation had no significant effect.
  
  
  CONCLUSIONS
  Colonoscopy has a considerable error rate for localization of colorectal cancer, especially when previous colorectal procedures have been performed. Adjunctive localizing techniques, such as endoscopic tattooing, should be strongly considered.
authors.affiliation: Department of Surgery, University of Vermont College of Medicine, 111 Colchester Avenue, Burlington, VT 05401, USA.
authors.forename: Nicole
authors.initials: N
authors.lastname: Piscatelli
authors.forename: Neil
authors.initials: N
authors.lastname: Hyman
authors.forename: Turner
authors.initials: T
authors.lastname: Osler
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003082:Colectomy; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies