title: Ki-ras proto-oncogene mutations in sporadic colorectal adenomas: relationship to histologic and clinical characteristics.
abstract: OBJECTIVE
  [corrected] The goal of this study was to examine the relationship between Ki-ras mutations in colorectal adenomas and characteristics of both the subject (age, gender, and family/personal history of colonic neoplasia) and the adenoma (multiplicity, size, location, and histologic features).
  
  
  METHODS
  Ki-ras mutations were detected by direct sequencing in 738 adenomatous polyps removed at baseline from 639 participants in a nutritional trial of adenoma recurrence.
  
  
  RESULTS
  Ki-ras mutations were detected in 17.2% of the adenomas. Ki-ras mutations were unrelated to gender, family, or personal history of colonic neoplasia, location within the colorectum, or adenoma multiplicity, but were more common in older subjects (P = 0.01 for trend), in larger adenomas (P < 0.0001 for trend), in adenomas with villous histology (odds ratio [OR], 3.2; 95% confidence interval [CI], 2.1-4.9 vs. tubular), and in adenomas with high-grade dysplasia (32.0% vs. 13.6%; OR, 3.0; 95% CI, 1.9-4.6 vs. low-grade dysplasia). Multivariate analysis showed Ki-ras mutations to be independently associated with subject age (P = 0.01 for trend), tubulovillous/villous histology (OR, 2.3; 95% CI, 1.5-3.7), and high-grade dysplasia (OR, 1.9; 95% CI, 1.2-3.1). Adenoma size was not independently related to Ki-ras mutation.
  
  
  CONCLUSIONS
  Ki-ras mutations are associated with the histologic features of adenoma progression (villous histology and high-grade dysplasia) rather than with adenoma growth.
authors.affiliation: Department of Veterans Affairs Medical Center, 111E, 1055 Clermont Street, Denver, Colorado 80220, USA.
authors.forename: T
authors.initials: T
authors.lastname: Maltzman
authors.forename: K
authors.initials: K
authors.lastname: Knoll
authors.forename: M E
authors.initials: ME
authors.lastname: Martinez
authors.forename: T
authors.initials: T
authors.lastname: Byers
authors.forename: B R
authors.initials: BR
authors.lastname: Stevens
authors.forename: J R
authors.initials: JR
authors.lastname: Marshall
authors.forename: M E
authors.initials: ME
authors.lastname: Reid
authors.forename: J
authors.initials: J
authors.lastname: Einspahr
authors.forename: N
authors.initials: N
authors.lastname: Hart
authors.forename: A K
authors.initials: AK
authors.lastname: Bhattacharyya
authors.forename: C B
authors.initials: CB
authors.lastname: Kramer
authors.forename: R
authors.initials: R
authors.lastname: Sampliner
authors.forename: D S
authors.initials: DS
authors.lastname: Alberts
authors.forename: D J
authors.initials: DJ
authors.lastname: Ahnen
mesh_terms: D000236:Adenoma / Q000235:genetics* / Q000473:pathology*; D000368:Aged; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000235:genetics* / Q000473:pathology*; D004252:DNA Mutational Analysis; D005260:Female; D011905:Genes, ras / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D009154:Mutation; D009364:Neoplasm Recurrence, Local; D015995:Prevalence; D000090063:Proto-Oncogene Mas