title: Identification of subjects at risk for colorectal carcinoma through a test based on K-ras determination in the stool.
abstract: OBJECTIVE
  The gold standard for screening for colorectal carcinoma is colonoscopy. The aim of this study was to compare endoscopic results with those obtained using the noninvasive screening test of K-ras determination in the stool in a large population of patients undergoing colonoscopy.
  
  
  METHODS
  Two hundred thirty consecutive patients were studied by K-ras amplification on stool-derived DNA using polymerase chain reaction and oligomer-specific hybridization.
  
  
  RESULTS
  Wild-type K-ras was amplified in 103 of 230 patients (44.8%), the rate of amplification being directly proportional to the presence of an organic disease of the intestine characterized by hyperproliferating mucosa. In 30 of these 103 patients (29.1%), a K-ras mutation was found. Four of 5 with early colorectal carcinoma, all who had K-ras mutations in the tumor, were identified. In first-degree relatives of patients with colorectal carcinoma, all subjects either carrying adenomas > 1 cm in diameter or multiple smaller adenomas were identified. In patients with inflammatory bowel disease, the test identified the only patient with neoplastic transformation.
  
  
  CONCLUSIONS
  The sensitivity and specificity of K-ras determination on stool-derived DNA in patients with colorectal carcinoma, in first-degree relatives of patients with colorectal carcinoma, and in patients with inflammatory bowel disease support the opportunity of a large-scale trial to validate its use as a screening test.
authors.affiliation: Department of Internal Medicine, University of Modena, Italy. Ericavil@unimail
authors.forename: E
authors.initials: E
authors.lastname: Villa
authors.forename: A
authors.initials: A
authors.lastname: Dugani
authors.forename: A M
authors.initials: AM
authors.lastname: Rebecchi
authors.forename: A
authors.initials: A
authors.lastname: Vignoli
authors.forename: A
authors.initials: A
authors.lastname: Grottola
authors.forename: P
authors.initials: P
authors.lastname: Buttafoco
authors.forename: L
authors.initials: L
authors.lastname: Losi
authors.forename: M
authors.initials: M
authors.lastname: Perini
authors.forename: P
authors.initials: P
authors.lastname: Trande
authors.forename: A
authors.initials: A
authors.lastname: Merighi
authors.forename: R
authors.initials: R
authors.lastname: Lerose
authors.forename: F
authors.initials: F
authors.lastname: Manenti
mesh_terms: D000236:Adenoma / Q000235:genetics / Q000517:prevention & control; D000328:Adult; D000368:Aged; D001483:Base Sequence; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000517:prevention & control; D004252:DNA Mutational Analysis; D005243:Feces / Q000737:chemistry*; D005260:Female; D005784:Gene Amplification; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000235:genetics; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012680:Sensitivity and Specificity