title: Benefits of colonoscopic surveillance and prophylactic colectomy in patients with hereditary nonpolyposis colorectal cancer mutations.
abstract: BACKGROUND
  Predisposition genetic testing is now possible for many hereditary cancer syndromes, including hereditary nonpolyposis colorectal cancer. The optimal management of the elevated risk for cancer in carriers of mutations for hereditary nonpolyposis colorectal cancer is unclear.
  
  
  OBJECTIVE
  To assess the life expectancy and quality-adjusted life expectancy benefits derived from endoscopic surveillance and prophylactic colectomy for persons who carry a mutation associated with hereditary nonpolyposis colorectal cancer.
  
  
  METHODS
  Decision analysis model. Lifetime risk for colorectal cancer, efficacy of surveillance and colectomy, stage-specific colorectal cancer mortality, and quality of life were included in the model.
  
  
  METHODS
  Decision about a cancer prevention strategy at the time of a positive result on genetic testing.
  
  
  METHODS
  Carriers of a mutation for hereditary nonpolyposis colorectal cancer who were 25 years of age.
  
  
  METHODS
  Immediate prophylactic colectomy; delayed colectomy on the basis of age, adenoma, or diagnosis of colorectal cancer; and endoscopic surveillance. Prophylactic surgical options were proctocolectomy with ileoanal anastomosis and subtotal colectomy with ileorectal anastomosis.
  
  
  METHODS
  Life expectancy and quality-adjusted life expectancy.
  
  
  RESULTS
  All risk-reduction strategies led to large gains in life expectancy for carriers of a mutation for hereditary nonpolyposis colorectal cancer, with benefits ranging from 13.5 years for surveillance to 15.6 years for prophylactic proctocolectomy at 25 years of age compared with no intervention. The benefits of colectomy compared with surveillance decreased with increasing age and were minimal if colectomy was performed at the time of colorectal cancer diagnosis. When health-related quality of life was considered, surveillance led to the greatest quality-adjusted life expectancy benefit (3.1 years compared with proctocolectomy and 0.3 years compared with subtotal colectomy).
  
  
  CONCLUSIONS
  Colonoscopic surveillance is an effective method of reducing risk for cancer in carriers of a mutation for hereditary nonpolyposis colorectal cancer. The individual patient's choice between prophylactic surgery and surveillance is a complex decision in which personal preferences weigh heavily.
authors.affiliation: Brigham and Women's Hospital, and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: S
authors.initials: S
authors.lastname: Syngal
authors.forename: J C
authors.initials: JC
authors.lastname: Weeks
authors.forename: D
authors.initials: D
authors.lastname: Schrag
authors.forename: J E
authors.initials: JE
authors.lastname: Garber
authors.forename: K M
authors.initials: KM
authors.lastname: Kuntz
mesh_terms: D000328:Adult; D000368:Aged; D000714:Anastomosis, Surgical; D003082:Colectomy; D003113:Colonoscopy; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000235:genetics / Q000401:mortality / Q000517:prevention & control*; D003661:Decision Support Techniques; D006579:Heterozygote; D006801:Humans; D007082:Ileum / Q000601:surgery; D008017:Life Expectancy; D008390:Markov Chains; D008875:Middle Aged; D009154:Mutation; D016737:Proctocolectomy, Restorative; D019057:Quality-Adjusted Life Years; D012007:Rectum / Q000601:surgery; D012680:Sensitivity and Specificity