title: Cost-effectiveness of laparoscopy versus laparotomy for initial surgical evaluation and treatment of potentially resectable hepatic colorectal metastases: a decision analysis.
abstract: OBJECTIVE
  Approximately 10-40% of colorectal cancer patients with potentially resectable hepatic metastases are incorrectly deemed resectable on standard pre-operative evaluation, including contrast-enhanced CT. Laparoscopy can identify unresectability in a majority of patients at highest risk of being incorrectly deemed resectable, sparing them an unnecessary laparotomy. However, laparoscopy requires an added investment by surgeons, patients, and payers. This analysis seeks to ascertain whether that investment is cost-effective.
  
  
  METHODS
  A decision tree model was developed to evaluate the societal cost-effectiveness of laparoscopy versus laparotomy in colorectal cancer patients with hepatic metastases deemed resectable on standard pre-operative evaluation. This comparison involved the cost, the effectiveness, and the incremental cost-effectiveness (the cost in dollars for each quality-adjusted life-year saved) of each option. Sensitivity analysis was performed to evaluate the model's validity under a variety of assumptions.
  
  
  RESULTS
  The cost-effectiveness of performing laparoscopy prior to laparotomy for resection of colorectal hepatic metastases depends primarily upon the probability of resectability determined at laparoscopy, and on the sensitivity of diagnostic laparoscopy.
  
  
  CONCLUSIONS
  Laparoscopy for initial evaluation of resectability of hepatic metastases from colorectal cancer is most likely to benefit patients and save costs when performed after pre-operative risk stratification in patients at high risk of radiographically occult unresectable disease.
authors.affiliation: Department of Surgery, Virginia Mason Medical Center, Seattle, WA 98101, USA. jstrekkers@hotmail.com
authors.forename: Shelly Tanner
authors.initials: ST
authors.lastname: Karuna
authors.forename: Richard
authors.initials: R
authors.lastname: Thirlby
authors.forename: Thomas
authors.initials: T
authors.lastname: Biehl
authors.forename: David
authors.initials: D
authors.lastname: Veenstra
mesh_terms: D015179:Colorectal Neoplasms / Q000401:mortality / Q000473:pathology*; D003362:Cost-Benefit Analysis; D003663:Decision Trees; D006760:Hospitalization / Q000191:economics; D006801:Humans; D010535:Laparoscopy / Q000191:economics*; D007813:Laparotomy / Q000191:economics*; D008113:Liver Neoplasms / Q000401:mortality / Q000556:secondary / Q000601:surgery*; D019057:Quality-Adjusted Life Years; D016019:Survival Analysis; D014481:United States