title: Decision model of segmental compared with total abdominal colectomy for colon cancer in hereditary nonpolyposis colorectal cancer.
abstract: OBJECTIVE
  In choosing the appropriate surgical option for patients with colon cancer and Lynch syndrome, goals of treatment are to maximize life expectancy while preserving quality of life. This study constructs a decision model that encompasses these two related considerations.
  
  
  METHODS
  We constructed a state-transition (Markov) model based on assumptions obtained from available data sources and published literature. Two strategies were considered for the treatment of colon cancer in a patient with Lynch syndrome: segmental colectomy (SEG) and total abdominal colectomy (TAC) with ileorectal anastomosis. Quality-adjusted life years (QALYs) were calculated based on utility states for patients based on the colectomy they received. Multiple sensitivity analyses were planned to examine the impact of each assumption on model results.
  
  
  RESULTS
  For young (30-year-old) patients with Lynch syndrome, mean survival was slightly better with TAC than with SEG (34.8 v 35.5 years). When QALYs were considered, the two strategies were approximately equivalent, with QALYs per patient of 21.5 for SEG and 21.2 for TAC. With advancing age, SEG becomes a more favorable strategy. Results of our model were most sensitive to the utility state of TAC (relative to SEG), rates of metachronous occurrence, and stage of cancer at the time of such occurrence.
  
  
  CONCLUSIONS
  SEG and TAC are approximately equivalent strategies for patients with colon cancer and Lynch syndrome. The decision regarding which operation is preferable should be made on the basis of patient factors and preferences, with special emphasis on age and the ability of the patient to utilize intensive surveillance.
authors.affiliation: MSHS, Department of Surgery/Division of Colorectal Surgery, Keck School of Medicine/University of Southern California, 1441 Eastlake Ave, Ste 7418, Los Angeles, CA 90033, USA.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Maeda
authors.forename: Rebecca R
authors.initials: RR
authors.lastname: Cannom
authors.forename: Robert W
authors.initials: RW
authors.lastname: Beart
authors.forename: David A
authors.initials: DA
authors.lastname: Etzioni
mesh_terms: D000328:Adult; D000368:Aged; D003082:Colectomy / Q000379:methods*; D003110:Colonic Neoplasms / Q000453:epidemiology / Q000401:mortality / Q000601:surgery*; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000401:mortality / Q000601:surgery*; D003661:Decision Support Techniques; D006801:Humans; D008390:Markov Chains; D008875:Middle Aged; D019057:Quality-Adjusted Life Years