title: Utility of relative and absolute measures of mammographic density vs clinical risk factors in evaluating breast cancer risk at time of screening mammography.
abstract: OBJECTIVE
  Various clinical risk factors, including high breast density, have been shown to be associated with breast cancer. The utility of using relative and absolute area-based breast density-related measures was evaluated as an alternative to clinical risk factors in cancer risk assessment at the time of screening mammography.
  
  
  METHODS
  Contralateral mediolateral oblique digital mammography images from 392 females with unilateral breast cancer and 817 age-matched controls were analysed. Information on clinical risk factors was obtained from the provincial breast-imaging information system. Breast density-related measures were assessed using a fully automated breast density measurement software. Multivariable logistic regression was conducted, and area under the receiver-operating characteristic (AUROC) curve was used to evaluate the performance of three cancer risk models: the first using only clinical risk factors, the second using only density-related measures and the third using both clinical risk factors and density-related measures.
  
  
  RESULTS
  The risk factor-based model generated an AUROC of 0.535, while the model including only breast density-related measures generated a significantly higher AUROC of 0.622 (p < 0.001). The third combined model generated an AUROC of 0.632 and performed significantly better than the risk factor model (p < 0.001) but not the density-related measures model (p = 0.097).
  
  
  CONCLUSIONS
  Density-related measures from screening mammograms at the time of screen may be superior predictors of cancer compared with clinical risk factors.
  
  
  CONCLUSIONS
  Breast cancer risk models based on density-related measures alone can outperform risk models based on clinical factors. Such models may support the development of personalized breast-screening protocols.
authors.affiliation: 1 Department of Diagnostic Radiology, Dalhousie University, Halifax, NS, Canada.|2 Department of Diagnostic Imaging, Nova Scotia Health Authority, Halifax, NS, Canada.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abdolell
authors.affiliation: 2 Department of Diagnostic Imaging, Nova Scotia Health Authority, Halifax, NS, Canada.
authors.forename: Kaitlyn M
authors.initials: KM
authors.lastname: Tsuruda
authors.affiliation: 1 Department of Diagnostic Radiology, Dalhousie University, Halifax, NS, Canada.|2 Department of Diagnostic Imaging, Nova Scotia Health Authority, Halifax, NS, Canada.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Lightfoot
authors.affiliation: 1 Department of Diagnostic Radiology, Dalhousie University, Halifax, NS, Canada.|3 Nova Scotia Breast Screening Program, Halifax, NS, Canada.|4 Department of Community Health and Epidemiology, Dalhousie University, Halifax, NS, Canada.
authors.forename: Jennifer I
authors.initials: JI
authors.lastname: Payne
authors.affiliation: 1 Department of Diagnostic Radiology, Dalhousie University, Halifax, NS, Canada.|2 Department of Diagnostic Imaging, Nova Scotia Health Authority, Halifax, NS, Canada.|3 Nova Scotia Breast Screening Program, Halifax, NS, Canada.
authors.forename: Judy S
authors.initials: JS
authors.lastname: Caines
authors.affiliation: 1 Department of Diagnostic Radiology, Dalhousie University, Halifax, NS, Canada.|2 Department of Diagnostic Imaging, Nova Scotia Health Authority, Halifax, NS, Canada.
authors.forename: Sian E
authors.initials: SE
authors.lastname: Iles
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D000071060:Breast Density; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D042361:Mammary Glands, Human / Q000002:abnormalities*; D008875:Middle Aged; D011859:Radiography; D018570:Risk Assessment; D012307:Risk Factors