title: Semi-automated and fully automated mammographic density measurement and breast cancer risk prediction.
abstract: The task of breast density quantification is becoming increasingly relevant due to its association with breast cancer risk. In this work, a semi-automated and a fully automated tools to assess breast density from full-field digitized mammograms are presented. The first tool is based on a supervised interactive thresholding procedure for segmenting dense from fatty tissue and is used with a twofold goal: for assessing mammographic density (MD) in a more objective and accurate way than via visual-based methods and for labeling the mammograms that are later employed to train the fully automated tool. Although most automated methods rely on supervised approaches based on a global labeling of the mammogram, the proposed method relies on pixel-level labeling, allowing better tissue classification and density measurement on a continuous scale. The fully automated method presented combines a classification scheme based on local features and thresholding operations that improve the performance of the classifier. A dataset of 655 mammograms was used to test the concordance of both approaches in measuring MD. Three expert radiologists measured MD in each of the mammograms using the semi-automated tool (DM-Scan). It was then measured by the fully automated system and the correlation between both methods was computed. The relation between MD and breast cancer was then analyzed using a case-control dataset consisting of 230 mammograms. The Intraclass Correlation Coefficient (ICC) was used to compute reliability among raters and between techniques. The results obtained showed an average ICC=0.922 among raters when using the semi-automated tool, whilst the average correlation between the semi-automated and automated measures was ICC=0.838. In the case-control study, the results obtained showed Odds Ratios (OR) of 1.38 and 1.50 per 10% increase in MD when using the semi-automated and fully automated approaches respectively. It can therefore be concluded that the automated and semi-automated MD assessments present a good correlation. Both the methods also found an association between MD and breast cancer risk, which warrants the proposed tools for breast cancer risk prediction and clinical decision making. A full version of the DM-Scan is freely available.
authors.affiliation: Institute of Computer Technology, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain. Electronic address: rllobet@iti.upv.es.
authors.forename: Rafael
authors.initials: R
authors.lastname: Llobet
authors.affiliation: National Center for Epidemiology, Carlos III Institute of Health, Monforte de Lemos 5, Madrid 28029, Spain; Consortium for Biomedical Research in Epidemiology and Public Health (CIBER en Epidemiología y Salud Pública - CIBERESP), Carlos III Institute of Health, Monforte de Lemos 5, Madrid 28029, Spain. Electronic address: mpollan@isciii.es.
authors.forename: Marina
authors.initials: M
authors.lastname: Pollán
authors.affiliation: Institute of Computer Technology, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain. Electronic address: j.anton.guirao@gmail.com.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Antón
authors.affiliation: Valencian Breast Cancer Screening Program, General Directorate of Public Health, Valencia, Spain; Centro Superior de Investigación en Salud Pública CSISP, FISABIO, Valencia, Spain. Electronic address: miranda_mjo@gva.es.
authors.forename: Josefa
authors.initials: J
authors.lastname: Miranda-García
authors.affiliation: Valencian Breast Cancer Screening Program, General Directorate of Public Health, Valencia, Spain; Centro Superior de Investigación en Salud Pública CSISP, FISABIO, Valencia, Spain. Electronic address: casals_mar@gva.es.
authors.forename: María
authors.initials: M
authors.lastname: Casals
authors.affiliation: Valencian Breast Cancer Screening Program, General Directorate of Public Health, Valencia, Spain; Centro Superior de Investigación en Salud Pública CSISP, FISABIO, Valencia, Spain. Electronic address: martinez_inm@gva.es.
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Martínez
authors.affiliation: Valencian Breast Cancer Screening Program, General Directorate of Public Health, Valencia, Spain; Centro Superior de Investigación en Salud Pública CSISP, FISABIO, Valencia, Spain. Electronic address: pruizp@comv.es.
authors.forename: Francisco
authors.initials: F
authors.lastname: Ruiz-Perales
authors.affiliation: Institute of Computer Technology, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain; National Center for Epidemiology, Carlos III Institute of Health, Monforte de Lemos 5, Madrid 28029, Spain. Electronic address: bperez@isciii.es.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Pérez-Gómez
authors.affiliation: Valencian Breast Cancer Screening Program, General Directorate of Public Health, Valencia, Spain; Centro Superior de Investigación en Salud Pública CSISP, FISABIO, Valencia, Spain. Electronic address: salas_dol@gva.es.
authors.forename: Dolores
authors.initials: D
authors.lastname: Salas-Trejo
authors.affiliation: Institute of Computer Technology, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain. Electronic address: jcperez@iti.upv.es.
authors.forename: Juan-Carlos
authors.initials: JC
authors.lastname: Pérez-Cortés
mesh_terms: D000368:Aged; D001331:Automation / Q000706:statistics & numerical data; D000071060:Breast Density; D001943:Breast Neoplasms / Q000145:classification / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D016208:Databases, Factual / Q000706:statistics & numerical data; D003936:Diagnosis, Computer-Assisted / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D042361:Mammary Glands, Human / Q000002:abnormalities*; D008327:Mammography / Q000706:statistics & numerical data*; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012307:Risk Factors
keywords: Automated density assessment; Breast cancer risk; Computer image analysis; Computer-aided diagnosis; Mammographic density