title: Relationship of Predicted Risk of Developing Invasive Breast Cancer, as Assessed with Three Models, and Breast Cancer Mortality among Breast Cancer Patients.
abstract: OBJECTIVE
  Breast cancer risk prediction models are used to plan clinical trials and counsel women; however, relationships of predicted risks of breast cancer incidence and prognosis after breast cancer diagnosis are unknown.
  
  
  METHODS
  Using largely pre-diagnostic information from the Breast Cancer Surveillance Consortium (BCSC) for 37,939 invasive breast cancers (1996-2007), we estimated 5-year breast cancer risk (<1%; 1-1.66%; ≥1.67%) with three models: BCSC 1-year risk model (BCSC-1; adapted to 5-year predictions); Breast Cancer Risk Assessment Tool (BCRAT); and BCSC 5-year risk model (BCSC-5). Breast cancer-specific mortality post-diagnosis (range: 1-13 years; median: 5.4-5.6 years) was related to predicted risk of developing breast cancer using unadjusted Cox proportional hazards models, and in age-stratified (35-44; 45-54; 55-69; 70-89 years) models adjusted for continuous age, BCSC registry, calendar period, income, mode of presentation, stage and treatment. Mean age at diagnosis was 60 years.
  
  
  RESULTS
  Of 6,021 deaths, 2,993 (49.7%) were ascribed to breast cancer. In unadjusted case-only analyses, predicted breast cancer risk ≥1.67% versus <1.0% was associated with lower risk of breast cancer death; BCSC-1: hazard ratio (HR) = 0.82 (95% CI = 0.75-0.90); BCRAT: HR = 0.72 (95% CI = 0.65-0.81) and BCSC-5: HR = 0.84 (95% CI = 0.75-0.94). Age-stratified, adjusted models showed similar, although mostly non-significant HRs. Among women ages 55-69 years, HRs approximated 1.0. Generally, higher predicted risk was inversely related to percentages of cancers with unfavorable prognostic characteristics, especially among women 35-44 years.
  
  
  CONCLUSIONS
  Among cases assessed with three models, higher predicted risk of developing breast cancer was not associated with greater risk of breast cancer death; thus, these models would have limited utility in planning studies to evaluate breast cancer mortality reduction strategies. Further, when offering women counseling, it may be useful to note that high predicted risk of developing breast cancer does not imply that if cancer develops it will behave aggressively.
authors: National Cancer Institute, Division of Cancer Prevention and Division of Cancer Epidemiology and Genetics, Bethesda, Maryland, United States of America.
authors: Mark E
authors: ME
authors: Sherman
authors: Group Health Research Institute, Group Health Cooperative, Seattle, Washington, United States of America.
authors: Laura
authors: L
authors: Ichikawa
authors: Division of Cancer Epidemiology and Genetics, Bethesda, United States of America.
authors: Ruth M
authors: RM
authors: Pfeiffer
authors: Group Health Research Institute, Group Health Cooperative, Seattle, Washington, United States of America.|University of California Davis, Department of Public Health, Davis, California, United States of America.
authors: Diana L
authors: DL
authors: Miglioretti
authors: University of California San Francisco, Department of Medicine and Department of Epidemiology/Biostatistics, San Francisco, California, United States of America.
authors: Karla
authors: K
authors: Kerlikowske
authors: University of California at San Francisco, Department of Medicine, San Francisco, United States of America.
authors: Jeffery
authors: J
authors: Tice
authors: University of Vermont School of Medicine, Department of Medical Biostatistics, Burlington, Vermont, United States of America.
authors: Pamela M
authors: PM
authors: Vacek
authors: Division of Cancer Epidemiology and Genetics, Bethesda, United States of America.
authors: Gretchen L
authors: GL
authors: Gierach
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000401:mortality*; D002986:Clinical Trials as Topic; D005260:Female; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D008962:Models, Theoretical; D009361:Neoplasm Invasiveness; D011379:Prognosis; D016016:Proportional Hazards Models; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D014481:United States