title: The type of K-ras mutation determines prognosis in colorectal cancer.
abstract: BACKGROUND
  Mutations involving the oncogene K-ras in colorectal cancer may be related to tumor aggressiveness. However, the value of K-ras gene determination as a prognostic marker has not been clearly established.
  
  
  METHODS
  The results from 98 patients recruited in a prospective study analyzing the effect of a K-ras mutation as a prognostic factor in colorectal cancer are reported.
  
  
  RESULTS
  Disease-free (P = 0.02) and overall survival (P = 0.03) were significantly reduced for patients harboring a K-ras mutation. Two specific mutations demonstrated a significantly increased risk of disease recurrence, namely, 12-TGT (P = 0.04) and 13-GAC substitutions (P = 0.002). Patients with either of these substitutions had a 2-year disease-free survival rate of 37% compared with that of 67% for the group of patients harboring any other mutation type or a wild-type status (P = 0.01).
  
  
  CONCLUSIONS
  The results herein presented suggest that K-ras acts as a prognostic factor in colorectal cancer and that this effect is probably related to a limited number of defined mutations.
authors.affiliation: Department of Surgery, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
authors.forename: J P
authors.initials: JP
authors.lastname: Cerottini
authors.forename: S
authors.initials: S
authors.lastname: Caplin
authors.forename: E
authors.initials: E
authors.lastname: Saraga
authors.forename: J C
authors.initials: JC
authors.lastname: Givel
authors.forename: J
authors.initials: J
authors.lastname: Benhattar
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000401:mortality* / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D011379:Prognosis; D011446:Prospective Studies; D016019:Survival Analysis