Affiliations 

  • 1 Section of Environment and Radiation, International Agency for Research on Cancer, Lyon, France. Electronic address: mccormackv@iarc.fr
  • 2 Section of Environment and Radiation, International Agency for Research on Cancer, Lyon, France
  • 3 Dept of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
  • 4 Centre for Medical Image Computing, University College London, UK
  • 5 University of the Witwatersrand, South Africa
  • 6 Cairo University, Egypt
  • 7 Woman Imaging Unit, Radiodiagnosis Department, Kasr El Aini, Cairo University Hospitals, Cairo, Egypt
  • 8 Department of Surgery, Yong Loo Lin School of Medicine and Saw Swee Hock School of Public Health, National University of Singapore, Singapore
  • 9 Department of Surgery, Yong Loo Lin School of Medicine and Saw Swee Hock School of Public Health, National University of Singapore, Singapore; NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
  • 10 NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
  • 11 Istanbul University, Turkey
  • 12 National Cancer Control Center, Israel
  • 13 Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, USA; Center for Research on Population Health, Instituto Nacional de Salud Pública, Mexico, Mexico City, Mexico
  • 14 Center for Research on Population Health, Instituto Nacional de Salud Pública, Mexico, Mexico City, Mexico
  • 15 Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, USA
  • 16 Section of Nutrition and Metabolism, International Agency for Research on Cancer, Lyon, France
  • 17 Cancer Registry of Norway, Oslo, Norway; Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway; Department of Preventive Medicine, University of Southern California, Los Angeles, California, USA
  • 18 Norwegian Center for Minority Health Research (NAKMI), Oslo, Norway
  • 19 Department of Population Sciences, Beckman Research Institute, City of Hope, Duarte, USA
  • 20 Department of Preventive Medicine, University of Southern California, Los Angeles, California, USA
  • 21 Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands
  • 22 Aga Khan University Hospital, Nairobi, Kenya
  • 23 Department of Imaging, Royal Marsden NHS Foundation Trust, London, UK
  • 24 Division of Cancer Research, Ninewells Hospital & Medical School, Dundee, UK
  • 25 Wolfson Institute of Preventive Medicine, Queen Mary University of London, UK
  • 26 Asan Medical Center, Seoul, Republic of Korea
  • 27 Institute of Nutrition and Food Technology, University of Chile, Chile
  • 28 Isfahan University of Medical Sciences, Isfahan, Iran
  • 29 Nofer Institute of Occupational Medicine, Łódź, Poland
  • 30 Slone Epidemiology Center, Boston University, Boston, MA, USA
  • 31 Gifu University, Gifu, Japan
  • 32 Division of Breast Surgery, The University of Hong Kong Faculty of Medicine, and Department of Surgery, Hong Kong Sanatorium and Hospital, Hong Kong, People's Republic of China
  • 33 Dept Health Sciences Research, Mayo Clinic, Rochester, Minnesota, USA
  • 34 Cancer Epidemiology Unit, Instituto de Salud Carlos III and CIBERESP, Madrid, Spain
  • 35 University of Hawaii Cancer Center, Honolulu, Hawaii, USA
  • 36 Cancer Epidemiology Centre, Cancer Council Victoria, Melbourne, Australia; School of Population and Global Health, The University of Melbourne, Australia
  • 37 School of Population and Global Health, The University of Melbourne, Australia
  • 38 Centre for Genetic Origins of Health and Disease, University of Western Australia, Australia
  • 39 Breast Cancer Research Group, University Malaya Medical Centre, University Malaya, Kuala Lumpur, Malaysia
  • 40 Breast Cancer Research Group, University Malaya Medical Centre, University Malaya, Kuala Lumpur, Malaysia; Cancer Research Malaysia, Subang Jaya, Malaysia
  • 41 Medical Biophysics, University of Toronto, Canada
  • 42 Ontario Breast Screening Program, Cancer Care Ontario, Toronto, Canada
  • 43 Princess Margaret Cancer Centre, Toronto, Canada
Cancer Epidemiol, 2016 Feb;40:141-51.
PMID: 26724463 DOI: 10.1016/j.canep.2015.11.015

Abstract

Mammographic density (MD) is a quantitative trait, measurable in all women, and is among the strongest markers of breast cancer risk. The population-based epidemiology of MD has revealed genetic, lifestyle and societal/environmental determinants, but studies have largely been conducted in women with similar westernized lifestyles living in countries with high breast cancer incidence rates. To benefit from the heterogeneity in risk factors and their combinations worldwide, we created an International Consortium on Mammographic Density (ICMD) to pool individual-level epidemiological and MD data from general population studies worldwide. ICMD aims to characterize determinants of MD more precisely, and to evaluate whether they are consistent across populations worldwide. We included 11755 women, from 27 studies in 22 countries, on whom individual-level risk factor data were pooled and original mammographic images were re-read for ICMD to obtain standardized comparable MD data. In the present article, we present (i) the rationale for this consortium; (ii) characteristics of the studies and women included; and (iii) study methodology to obtain comparable MD data from original re-read films. We also highlight the risk factor heterogeneity captured by such an effort and, thus, the unique insight the pooled study promises to offer through wider exposure ranges, different confounding structures and enhanced power for sub-group analyses.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.