title: Economic model of observation versus immediate resection of hepatic adenomas.
abstract: OBJECTIVE
  For small asymptomatic hepatic adenomas (HA), available data are insufficient to establish the superiority of either observation or surgery. We sought to investigate the cost-effectiveness of two initial management strategies.
  
  
  METHODS
  We performed a comparative analysis of two theoretical cohorts of 100 patients with small (<5 cm), asymptomatic HA. Discounted cash flow (DCF) models compared the net present value (NPV) of both treatment options at year 10 under three distinct progression rate scenarios. A break-even (BE) analysis was used to determine the BE point at which the NPV for observation and immediate surgery intersect.
  
  
  RESULTS
  The NPV for immediate surgery was $1,733,955. The NPV for observation varied between $2,065,315-$2,745,631 for computed tomography (CT), $2,264,575-$2,929,541 for magnetic resonance imaging (MRI), and $802,837-$1,580,413 for ultrasound (US). The BE point was between 6 and 8 years for CT and 5-7 years for MRI. The BE point for US was not reached except in the highest progression rate scenario (12 years).
  
  
  CONCLUSIONS
  This study highlights the importance of the underlying progression rate and the cost of imaging when following patients with asymptomatic HA. Overall, US surveillance is the most cost-efficient approach to observing small asymptomatic HA. If cross-sectional imaging is utilized, then immediate surgery is the most cost-effective decision at 5-8 years.
authors.affiliation: Department of Surgery, McGill University, Jewish General Hospital, Montreal, Quebec, Canada.
authors.forename: Tsafrir
authors.initials: T
authors.lastname: Vanounou
authors.forename: Ryan T
authors.initials: RT
authors.lastname: Groeschl
authors.forename: David A
authors.initials: DA
authors.lastname: Geller
authors.forename: J Wallis
authors.initials: JW
authors.lastname: Marsh
authors.forename: T Clark
authors.initials: TC
authors.lastname: Gamblin
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000601:surgery*; D015331:Cohort Studies; D017048:Health Care Costs; D006801:Humans; D008113:Liver Neoplasms / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D018803:Models, Economic; D014057:Tomography, X-Ray Computed