title: Progression criteria for cancer antigen 15.3 and carcinoembryonic antigen in metastatic breast cancer compared by computer simulation of marker data.
abstract: BACKGROUND
  We investigated the utility of computer simulation models for performance comparisons of different tumor marker assessment criteria to define progression or nonprogression of metastatic breast cancer.
  
  
  METHODS
  Clinically relevant values for progressive cancer antigen 15.3 and carcinoembryonic antigen concentrations were combined with representative values for background variations in a computer simulation model. Fifteen criteria for assessment of longitudinal tumor marker data were obtained from the literature and computerized. Altogether, 7200 different patients, each based on 50 measurements, were simulated. With a sampling interval of 4 weeks, the monitoring period for each event was approximately 3.8 years.
  
  
  RESULTS
  Modulation of the background variation, the starting concentrations, and the cutoffs enabled identification of criteria that were robust against false-positive signals of progression.
  
  
  CONCLUSIONS
  The computer simulation model is a fast, effective, and inexpensive approach for comparing the diagnostic potential of assessment criteria during clinically relevant conditions of steady-state and progressive disease. The model systems can be used to generate tumor marker assessment criteria for a variety of malignancies and to compare and optimize their diagnostic performance.
authors.affiliation: Department of Clinical Biochemistry, Herlev Hospital, University of Copenhagen, 2720 Copenhagen, Denmark. geso@fa.dk
authors.forename: G
authors.initials: G
authors.lastname: Sölétormos
authors.forename: P
authors.initials: P
authors.lastname: Hyltoft Petersen
authors.forename: P
authors.initials: P
authors.lastname: Dombernowsky
mesh_terms: D001943:Breast Neoplasms / Q000175:diagnosis / Q000473:pathology*; D002272:Carcinoembryonic Antigen / Q000032:analysis*; D003198:Computer Simulation; D018450:Disease Progression; D005260:Female; D006801:Humans; D018396:Mucin-1 / Q000032:analysis*; D009362:Neoplasm Metastasis; D012016:Reference Values; D012984:Software
chemical_list: D002272:Carcinoembryonic Antigen; D018396:Mucin-1