1
|
Yarmolinsky J, Relton CL, Lophatananon A, Muir K, Menon U, Gentry-Maharaj A, Walther A, Zheng J, Fasching P, Zheng W, Yin Ling W, Park SK, Kim BG, Choi JY, Park B, Davey Smith G, Martin RM, Lewis SJ. Appraising the role of previously reported risk factors in epithelial ovarian cancer risk: A Mendelian randomization analysis. PLoS Med 2019; 16:e1002893. [PMID: 31390370 PMCID: PMC6685606 DOI: 10.1371/journal.pmed.1002893] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 07/15/2019] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Various risk factors have been associated with epithelial ovarian cancer risk in observational epidemiological studies. However, the causal nature of the risk factors reported, and thus their suitability as effective intervention targets, is unclear given the susceptibility of conventional observational designs to residual confounding and reverse causation. Mendelian randomization (MR) uses genetic variants as proxies for risk factors to strengthen causal inference in observational studies. We used MR to evaluate the association of 12 previously reported risk factors (reproductive, anthropometric, clinical, lifestyle, and molecular factors) with risk of invasive epithelial ovarian cancer, invasive epithelial ovarian cancer histotypes, and low malignant potential tumours. METHODS AND FINDINGS Genetic instruments to proxy 12 risk factors were constructed by identifying single nucleotide polymorphisms (SNPs) that were robustly (P < 5 × 10-8) and independently associated with each respective risk factor in previously reported genome-wide association studies. These risk factors included genetic liability to 3 factors (endometriosis, polycystic ovary syndrome, type 2 diabetes) scaled to reflect a 50% higher odds liability to disease. We obtained summary statistics for the association of these SNPs with risk of overall and histotype-specific invasive epithelial ovarian cancer (22,406 cases; 40,941 controls) and low malignant potential tumours (3,103 cases; 40,941 controls) from the Ovarian Cancer Association Consortium (OCAC). The OCAC dataset comprises 63 genotyping project/case-control sets with participants of European ancestry recruited from 14 countries (US, Australia, Belarus, Germany, Belgium, Denmark, Finland, Norway, Canada, Poland, UK, Spain, Netherlands, and Sweden). SNPs were combined into multi-allelic inverse-variance-weighted fixed or random effects models to generate effect estimates and 95% confidence intervals (CIs). Three complementary sensitivity analyses were performed to examine violations of MR assumptions: MR-Egger regression and weighted median and mode estimators. A Bonferroni-corrected P value threshold was used to establish strong evidence (P < 0.0042) and suggestive evidence (0.0042 < P < 0.05) for associations. In MR analyses, there was strong or suggestive evidence that 2 of the 12 risk factors were associated with invasive epithelial ovarian cancer and 8 of the 12 were associated with 1 or more invasive epithelial ovarian cancer histotypes. There was strong evidence that genetic liability to endometriosis was associated with an increased risk of invasive epithelial ovarian cancer (odds ratio [OR] per 50% higher odds liability: 1.10, 95% CI 1.06-1.15; P = 6.94 × 10-7) and suggestive evidence that lifetime smoking exposure was associated with an increased risk of invasive epithelial ovarian cancer (OR per unit increase in smoking score: 1.36, 95% CI 1.04-1.78; P = 0.02). In analyses examining histotypes and low malignant potential tumours, the strongest associations found were between height and clear cell carcinoma (OR per SD increase: 1.36, 95% CI 1.15-1.61; P = 0.0003); age at natural menopause and endometrioid carcinoma (OR per year later onset: 1.09, 95% CI 1.02-1.16; P = 0.007); and genetic liability to polycystic ovary syndrome and endometrioid carcinoma (OR per 50% higher odds liability: 0.89, 95% CI 0.82-0.96; P = 0.002). There was little evidence for an association of genetic liability to type 2 diabetes, parity, or circulating levels of 25-hydroxyvitamin D and sex hormone binding globulin with ovarian cancer or its subtypes. The primary limitations of this analysis include the modest statistical power for analyses of risk factors in relation to some less common ovarian cancer histotypes (low grade serous, mucinous, and clear cell carcinomas), the inability to directly examine the association of some ovarian cancer risk factors that did not have robust genetic variants available to serve as proxies (e.g., oral contraceptive use, hormone replacement therapy), and the assumption of linear relationships between risk factors and ovarian cancer risk. CONCLUSIONS Our comprehensive examination of possible aetiological drivers of ovarian carcinogenesis using germline genetic variants to proxy risk factors supports a role for few of these factors in invasive epithelial ovarian cancer overall and suggests distinct aetiologies across histotypes. The identification of novel risk factors remains an important priority for the prevention of epithelial ovarian cancer.
Collapse
Affiliation(s)
- James Yarmolinsky
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, United Kingdom
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Caroline L. Relton
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, United Kingdom
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- National Institute for Health Research Bristol Biomedical Research Centre, University of Bristol and University Hospitals Bristol NHS Foundation Trust, Bristol, United Kingdom
| | - Artitaya Lophatananon
- Division of Population Health, Health Services Research and Primary Care, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Kenneth Muir
- Division of Population Health, Health Services Research and Primary Care, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Usha Menon
- MRC Clinical Trials Unit, Institute for Clinical Trials and Methodology, University College London, London, United Kingdom
| | - Aleksandra Gentry-Maharaj
- MRC Clinical Trials Unit, Institute for Clinical Trials and Methodology, University College London, London, United Kingdom
| | - Axel Walther
- Bristol Cancer Institute, University Hospitals Bristol NHS Foundation Trust, Bristol, United Kingdom
| | - Jie Zheng
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, United Kingdom
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Peter Fasching
- Department of Gynecology and Obstetrics, University Hospital Erlangen, Comprehensive Cancer Center Erlangen–EMN, Friedrich-Alexander University Erlangen–Nuremberg, Erlangen, Germany
| | - Wei Zheng
- Division of Epidemiology, Vanderbilt University Medical Center, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Woo Yin Ling
- Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Sue K. Park
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, South Korea
- Cancer Research Institute, Seoul National University, Seoul, South Korea
- Department of Biomedical Science, Seoul National University Graduate School, Seoul, South Korea
| | - Byoung-Gie Kim
- Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Ji-Yeob Choi
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, South Korea
- Cancer Research Institute, Seoul National University, Seoul, South Korea
- Department of Biomedical Science, Seoul National University Graduate School, Seoul, South Korea
| | - Boyoung Park
- Department of Medicine, College of Medicine, Hanyang University, Seoul, South Korea
| | - George Davey Smith
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, United Kingdom
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- National Institute for Health Research Bristol Biomedical Research Centre, University of Bristol and University Hospitals Bristol NHS Foundation Trust, Bristol, United Kingdom
| | - Richard M. Martin
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, United Kingdom
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- National Institute for Health Research Bristol Biomedical Research Centre, University of Bristol and University Hospitals Bristol NHS Foundation Trust, Bristol, United Kingdom
| | - Sarah J. Lewis
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, United Kingdom
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| |
Collapse
|
3
|
Doherty JA, Jensen A, Kelemen LE, Pearce CL, Poole E, Schildkraut JM, Terry KL, Tworoger SS, Webb PM, Wentzensen N. Current Gaps in Ovarian Cancer Epidemiology: The Need for New Population-Based Research. J Natl Cancer Inst 2017; 109:3847624. [PMID: 29117355 DOI: 10.1093/jnci/djx144] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 06/19/2017] [Indexed: 12/25/2022] Open
Abstract
With recent ovarian cancer screening studies showing no clinically significant mortality benefit, preventing this disease, identifying high-risk populations, and extending survival remain priorities. However, several challenges are impeding progress in ovarian cancer research. With most studies capturing exposure information from 10 or more years ago, evaluation of how changing patterns of exposures, such as new oral contraceptive formulations and increased intrauterine device use, might influence ovarian cancer risk and survival is difficult. Risk factors for ovarian cancer should be evaluated in the context of tumor histotypes, which have unique molecular features and cells of origin; this is a task that requires large collaborative studies to achieve meaningful sample sizes. Importantly, identification of novel modifiable risk factors, in addition to those currently known to reduce risk (eg, childbearing, tubal ligation, oral contraceptive use), is needed; this is not feasibly implemented at a population level. In this Commentary, we describe important gaps in knowledge and propose new approaches to advance epidemiologic research to improve ovarian cancer prevention and survival, including updated classification of tumors, collection of data on changing and novel exposures, longer follow-up on existing studies, evaluation of diverse populations, development of better risk prediction models, and collaborating prospectively with consortia to develop protocols for new studies that will allow seamless integration for future pooled analyses.
Collapse
Affiliation(s)
| | - Jennifer A Doherty
- Affiliations of authors: Huntsman Cancer Institute, Department of Population Health Sciences, University of Utah, Salt Lake City, UT (JAD); Department of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark (AJ); Department of Public Health Sciences and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (LEK); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI (CLP); Department of Preventive Medicine, Keck School of Medicine, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA (CLP); Channing Division of Network Medicine (EP, SST) and Obstetrics and Gynecology Epidemiology Center (KLT), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (EP, SST, KLT); Department of Public Health Sciences, University of Virginia, Charlottesville, CA (JMS); Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Australia (PMW); Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD (NW)
| | - Allan Jensen
- Affiliations of authors: Huntsman Cancer Institute, Department of Population Health Sciences, University of Utah, Salt Lake City, UT (JAD); Department of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark (AJ); Department of Public Health Sciences and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (LEK); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI (CLP); Department of Preventive Medicine, Keck School of Medicine, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA (CLP); Channing Division of Network Medicine (EP, SST) and Obstetrics and Gynecology Epidemiology Center (KLT), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (EP, SST, KLT); Department of Public Health Sciences, University of Virginia, Charlottesville, CA (JMS); Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Australia (PMW); Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD (NW)
| | - Linda E Kelemen
- Affiliations of authors: Huntsman Cancer Institute, Department of Population Health Sciences, University of Utah, Salt Lake City, UT (JAD); Department of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark (AJ); Department of Public Health Sciences and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (LEK); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI (CLP); Department of Preventive Medicine, Keck School of Medicine, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA (CLP); Channing Division of Network Medicine (EP, SST) and Obstetrics and Gynecology Epidemiology Center (KLT), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (EP, SST, KLT); Department of Public Health Sciences, University of Virginia, Charlottesville, CA (JMS); Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Australia (PMW); Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD (NW)
| | - Celeste L Pearce
- Affiliations of authors: Huntsman Cancer Institute, Department of Population Health Sciences, University of Utah, Salt Lake City, UT (JAD); Department of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark (AJ); Department of Public Health Sciences and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (LEK); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI (CLP); Department of Preventive Medicine, Keck School of Medicine, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA (CLP); Channing Division of Network Medicine (EP, SST) and Obstetrics and Gynecology Epidemiology Center (KLT), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (EP, SST, KLT); Department of Public Health Sciences, University of Virginia, Charlottesville, CA (JMS); Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Australia (PMW); Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD (NW)
| | - Elizabeth Poole
- Affiliations of authors: Huntsman Cancer Institute, Department of Population Health Sciences, University of Utah, Salt Lake City, UT (JAD); Department of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark (AJ); Department of Public Health Sciences and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (LEK); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI (CLP); Department of Preventive Medicine, Keck School of Medicine, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA (CLP); Channing Division of Network Medicine (EP, SST) and Obstetrics and Gynecology Epidemiology Center (KLT), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (EP, SST, KLT); Department of Public Health Sciences, University of Virginia, Charlottesville, CA (JMS); Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Australia (PMW); Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD (NW)
| | - Joellen M Schildkraut
- Affiliations of authors: Huntsman Cancer Institute, Department of Population Health Sciences, University of Utah, Salt Lake City, UT (JAD); Department of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark (AJ); Department of Public Health Sciences and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (LEK); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI (CLP); Department of Preventive Medicine, Keck School of Medicine, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA (CLP); Channing Division of Network Medicine (EP, SST) and Obstetrics and Gynecology Epidemiology Center (KLT), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (EP, SST, KLT); Department of Public Health Sciences, University of Virginia, Charlottesville, CA (JMS); Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Australia (PMW); Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD (NW)
| | - Kathryn L Terry
- Affiliations of authors: Huntsman Cancer Institute, Department of Population Health Sciences, University of Utah, Salt Lake City, UT (JAD); Department of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark (AJ); Department of Public Health Sciences and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (LEK); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI (CLP); Department of Preventive Medicine, Keck School of Medicine, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA (CLP); Channing Division of Network Medicine (EP, SST) and Obstetrics and Gynecology Epidemiology Center (KLT), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (EP, SST, KLT); Department of Public Health Sciences, University of Virginia, Charlottesville, CA (JMS); Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Australia (PMW); Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD (NW)
| | - Shelley S Tworoger
- Affiliations of authors: Huntsman Cancer Institute, Department of Population Health Sciences, University of Utah, Salt Lake City, UT (JAD); Department of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark (AJ); Department of Public Health Sciences and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (LEK); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI (CLP); Department of Preventive Medicine, Keck School of Medicine, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA (CLP); Channing Division of Network Medicine (EP, SST) and Obstetrics and Gynecology Epidemiology Center (KLT), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (EP, SST, KLT); Department of Public Health Sciences, University of Virginia, Charlottesville, CA (JMS); Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Australia (PMW); Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD (NW)
| | - Penelope M Webb
- Affiliations of authors: Huntsman Cancer Institute, Department of Population Health Sciences, University of Utah, Salt Lake City, UT (JAD); Department of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark (AJ); Department of Public Health Sciences and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (LEK); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI (CLP); Department of Preventive Medicine, Keck School of Medicine, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA (CLP); Channing Division of Network Medicine (EP, SST) and Obstetrics and Gynecology Epidemiology Center (KLT), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (EP, SST, KLT); Department of Public Health Sciences, University of Virginia, Charlottesville, CA (JMS); Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Australia (PMW); Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD (NW)
| | - Nicolas Wentzensen
- Affiliations of authors: Huntsman Cancer Institute, Department of Population Health Sciences, University of Utah, Salt Lake City, UT (JAD); Department of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark (AJ); Department of Public Health Sciences and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (LEK); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI (CLP); Department of Preventive Medicine, Keck School of Medicine, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA (CLP); Channing Division of Network Medicine (EP, SST) and Obstetrics and Gynecology Epidemiology Center (KLT), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA (EP, SST, KLT); Department of Public Health Sciences, University of Virginia, Charlottesville, CA (JMS); Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Australia (PMW); Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD (NW)
| |
Collapse
|