title: Breast cancer: computer simulation method for estimating optimal intervals for screening.
abstract: OBJECTIVE
  To develop and evaluate a mathematic method that can be used to determine the optimal screening interval for detection of breast cancer prior to distant metastatic spread.
  
  
  METHODS
  A computer simulation was developed with the use of biologically based data from the literature on the rates of tumor growth and spread, which can be used to calculate the course of breast cancer growth and metastasis.
  
  
  RESULTS
  On the basis of the data available at this time, the results of the simulations suggested that a screening interval of 2 years would result in a 22% reduction in the rate of distant metastatic disease, an interval of 1 year would result in a 51% reduction, and an interval of 6 months would result in an 80% reduction.
  
  
  CONCLUSIONS
  These findings suggest that more frequent screening could dramatically reduce the death rate from breast cancer.
authors.affiliation: Department of Pathology, Harvard Medical School, Boston, Mass., USA. michaelj@helix.mgh.harvard.edu
authors.forename: J S
authors.initials: JS
authors.lastname: Michaelson
authors.forename: E
authors.initials: E
authors.lastname: Halpern
authors.forename: D B
authors.initials: DB
authors.lastname: Kopans
mesh_terms: D001071:Appointments and Schedules; D001943:Breast Neoplasms / Q000453:epidemiology / Q000517:prevention & control*; D003198:Computer Simulation; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D015994:Incidence; D008327:Mammography / Q000706:statistics & numerical data; D008403:Mass Screening / Q000706:statistics & numerical data; D008875:Middle Aged; D008962:Models, Theoretical; D009362:Neoplasm Metastasis; D011336:Probability; D013997:Time Factors