title: Screening for Colorectal Cancer Using a Multitarget Stool DNA Test: Modeling the Effect of the Intertest Interval on Clinical Effectiveness.
abstract: A multitarget stool DNA (mt-sDNA) test was recently approved for colorectal cancer (CRC) screening for men and women, aged ≥ 50 years, at average risk of CRC. The guidelines currently recommend a 3-year interval for mt-sDNA testing in the absence of empirical data. We used clinical effectiveness modeling to project decreases in CRC incidence and related mortality associated with mt-sDNA screening to help inform interval setting.
  
  
  
  The Archimedes model (Archimedes Inc., San Francisco, CA) was used to conduct a 5-arm, virtual, clinical screening study of a population of 200,000 virtual individuals to compare the clinical effectiveness of mt-sDNA screening at 1-, 3-, and 5-year intervals compared with colonoscopy at 10-year intervals and no screening for a 30-year period. The study endpoints were the decrease in CRC incidence and related mortality of each strategy versus no screening. Cost-effectiveness ratios (US dollars per quality-adjusted life year [QALY]) of mt-sDNA intervals were calculated versus no screening.
  
  
  
  Compared with 10-year colonoscopy, annual mt-sDNA testing produced similar reductions in CRC incidence (65% vs. 63%) and related mortality (73% vs. 72%). mt-sDNA testing at 3-year intervals reduced the CRC incidence by 57% and CRC mortality by 67%, and mt-sDNA testing at 5-year intervals reduced the CRC incidence by 52% and CRC mortality by 62%. At an average price of $600 per test, the annual, 3-year, and 5-year mt-sDNA screening costs would be $20,178, $11,313, and $7388 per QALY, respectively, compared with no screening.
  
  
  
  These data suggest that screening every 3 years using a multitarget mt-sDNA test provides reasonable performance at acceptable cost.
authors.affiliation: Exact Sciences Corporation, Madison, WI. Electronic address: bbexact@yahoo.com.
authors.forename: Barry M
authors.initials: BM
authors.lastname: Berger
authors.affiliation: Department of Gastroenterology, Boston University School of Medicine, Boston, MA.
authors.forename: Paul C
authors.initials: PC
authors.lastname: Schroy
authors.affiliation: Archimedes Inc., San Francisco, CA.
authors.forename: Tuan A
authors.initials: TA
authors.lastname: Dinh
mesh_terms: D015179:Colorectal Neoplasms / Q000175:diagnosis*; D003362:Cost-Benefit Analysis; D004247:DNA / Q000032:analysis; D055088:Early Detection of Cancer / Q000191:economics / Q000379:methods*; D005243:Feces / Q000737:chemistry*; D006801:Humans; D008403:Mass Screening / Q000191:economics / Q000379:methods*; D008954:Models, Biological; D008962:Models, Theoretical
chemical_list: D004247:DNA
keywords: Archimedes; Colonoscopy; Guidelines; Model; Utility