Obesity and risk of ovarian cancer subtypes: evidence from the Ovarian Cancer Association Consortium

    1. Penelope M Webb the Ovarian Cancer Association Consortium1
    1. 1Queensland Institute of Medical Research, Royal Brisbane Hospital, Locked Bag 2000, Brisbane, Queensland 4029, Australia
      2School of Public Health, University of Texas, Houston, Texas, USA
      3Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
      4Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
      5Program in Epidemiology, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
      6Obstetrics and Gynecology Epidemiology Center, Brigham and Women's Hospital, Boston, Massachusetts, USA
      7Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
      8Department of Epidemiology and Public Health, School of Medicine, Yale University School of Public Health, 60 College Street, New Haven, Connecticut, USA
      9Cancer Epidemiology Program, University of Hawaii Cancer Center, Honolulu, Hawaii, USA
      10Division of Cancer Epidemiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
      11Department of Obstetrics and Gynecology, University of Ulm, Prittwitzstrasse 43, 89075 Ulm, Germany
      12Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
      13Department of Obstetrics and Gynecology, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii, USA
      14Roswell Park Cancer Center, Buffalo, New York, USA
      15Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark
      16Gynecologic Clinic, The Juliane Marie Centre, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
      17Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
      18Department of Community and Family Medicine, Duke University Medical Center, Durham, North Carolina, USA
      19Robert Wood Johnson Medical School, The Cancer Institute of New Jersey, New Brunswick, New Jersey, USA
      20School of Public Health, University of Medicine and Dentistry New Jersey, Piscataway, New Jersey, USA
      21National Cancer Institute, 6120 Executive Boulevard, Rockville, Maryland, USA
      22Division of Genetics and Epidemiology, Institute of Cancer Research, Belmont, Sutton, Surrey, UK
      23Department of Cancer Epidemiology and Prevention, The M Sklodowska-Curie Cancer Center and Institute of Oncology, WH Roentgena 5, Warsaw, Poland
      24Department of Epidemiology, School of Medicine, University of California, Irvine, California, USA
      25Department of Gynaecological Oncology, EGA Institute for Women's Health, University College London, UK
    1. Correspondence should be addressed to C M Olsen; Email: catherine.olsen{at}qimr.edu.au


    Whilst previous studies have reported that higher BMI increases a woman's risk of developing ovarian cancer, associations for the different histological subtypes have not been well defined. As the prevalence of obesity has increased dramatically, and classification of ovarian histology has improved in the last decade, we sought to examine the association in a pooled analysis of recent studies participating in the Ovarian Cancer Association Consortium. We evaluated the association between BMI (recent, maximum and in young adulthood) and ovarian cancer risk using original data from 15 case–control studies (13 548 cases and 17 913 controls). We combined study-specific adjusted odds ratios (ORs) using a random-effects model. We further examined the associations by histological subtype, menopausal status and post-menopausal hormone use. High BMI (all time-points) was associated with increased risk. This was most pronounced for borderline serous (recent BMI: pooled OR=1.24 per 5 kg/m2; 95% CI 1.18–1.30), invasive endometrioid (1.17; 1.11–1.23) and invasive mucinous (1.19; 1.06–1.32) tumours. There was no association with serous invasive cancer overall (0.98; 0.94–1.02), but increased risks for low-grade serous invasive tumours (1.13, 1.03–1.25) and in pre-menopausal women (1.11; 1.04–1.18). Among post-menopausal women, the associations did not differ between hormone replacement therapy users and non-users. Whilst obesity appears to increase risk of the less common histological subtypes of ovarian cancer, it does not increase risk of high-grade invasive serous cancers, and reducing BMI is therefore unlikely to prevent the majority of ovarian cancer deaths. Other modifiable factors must be identified to control this disease.

    • Revision received 3 February 2013
    • Accepted 5 February 2013
    • Made available online as an Accepted Preprint 12 February 2013
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