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PloS one2018; 13(5); e0197064; doi: 10.1371/journal.pone.0197064

Conjugated equine estrogen and medroxyprogesterone acetate are associated with decreased risk of breast cancer relative to bioidentical hormone therapy and controls.

Abstract: By the 1990s it became popular for women to use hormone therapy (HT) to ease menopause symptoms. Bioidentical estrogen and progesterone are supplements whose molecular structures are identical to what is made in the human body, while synthetic supplements are ones whose structures are not. After the Women's Health Initiative found that the combined use of the synthetics conjugated equine estrogen (CEE) and medroxyprogesterone acetate (MPA) increased breast cancer risk, prescriptions for synthetic HT declined considerably. Since then there has been an increased interest in bioidentical HT; today there are a plethora of websites touting their benefits. However, no peer-reviewed articles support these claims. We performed a retrospective study with the objective of verifying the hypothesis that bioidentical HT is associated with decreased breast cancer risk than CEE & MPA. We searched The Northwestern Medicine Enterprise Data Warehouse for women who initiated HT use after age 50. Women who did not take any HT drug after age 50 served as controls. Nine HT protocols were investigated for breast cancer risk. Significant results include CEE Alone is associated with decreased breast cancer risk (HR = 0.31), Other Synthetic Estrogen Alone is associated with increased breast cancer risk (HR = 1.49), Bioidentical Estrogen Alone is associated with decreased breast cancer risk(HR = 0.65), CEE & MPA is associated with reduced breast cancer risk (HR = 0.43), and CEE & MPA is associated with reduced breast cancer risk relative to Bioidentical Estrogen & Progesterone (HR = 0.25). Our results indicate CEE & MPA is superior to bioidentical HT as far as breast cancer risk. Furthermore, this combination is associated with decrease of breast cancer risk, contrary to previous findings. Additional retrospective studies are needed to confirm our results.
Publication Date: 2018-05-16 PubMed ID: 29768475PubMed Central: PMC5955567DOI: 10.1371/journal.pone.0197064Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • N.I.H.
  • Extramural

Summary

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This research indicates that the use of certain synthetic hormone therapies, specifically conjugated equine estrogen (CEE) and medroxyprogesterone acetate (MPA), may be linked to a decrease in the risk of breast cancer. This contradicts popular belief and previous studies that associate these synthetic hormones with an increased risk of developing the disease.

Objective and Context

  • This research was designed to challenge the widely held assumption that synthetic hormone therapy (HT), specifically CEE and MPA, increases the risk of breast cancer in post-menopausal women.
  • While synthetic hormone therapy was increasingly prescribed in the late 20th century to ease symptoms of menopause, concerns arose over their safety after the Women’s Health Initiative documented an increased breast cancer risk associated with combined use of CEE and MPA.
  • Preferring a more ‘natural’ approach, many women transitioned to bioidentical hormone therapy, which involves the usage of supplements identically structured to human-made hormones.
  • However, despite the rise in popularity of bioidentical therapies, no peer-reviewed studies were found to support claims of increased safety or efficacy over synthetic hormones – thus instigating this research.

Methods and Results

  • Researchers conducted a retrospective study to compare various hormone therapy regimens and their impacts on breast cancer risks.
  • They drew from a pool of women who began hormone therapies after the age of 50 and employed those who did not take any hormone therapy drugs after 50 as a control group.
  • Nine different hormone therapy protocols were examined for their association with breast cancer risk.
  • The findings demonstrated that certain synthetic hormone therapies contradicted the traditional belief of increasing breast cancer risk.
  • CEE alone and in combination with MPA indicated an association with decreased breast cancer risk compared to controls and bioidentical estrogen and progesterone therapies.
  • Contrarily, other synthetic estrogens, when used alone, demonstrated an increased risk of breast cancer compared to the control.

Implications and Conclusions

  • The study concludes that synthetic hormone therapy, CEE and MPA specifically, may potentially offer a lower risk of developing breast cancer compared to bioidentical hormone therapy or no hormone therapy at all, contradicting previous findings.
  • However, the authors caution that these findings are preliminary and require further retrospective studies to confirm these results before revisions can be made to existing hormone therapy guidelines.

Cite This Article

APA
Zeng Z, Jiang X, Li X, Wells A, Luo Y, Neapolitan R. (2018). Conjugated equine estrogen and medroxyprogesterone acetate are associated with decreased risk of breast cancer relative to bioidentical hormone therapy and controls. PLoS One, 13(5), e0197064. https://doi.org/10.1371/journal.pone.0197064

Publication

ISSN: 1932-6203
NlmUniqueID: 101285081
Country: United States
Language: English
Volume: 13
Issue: 5
Pages: e0197064
PII: e0197064

Researcher Affiliations

Zeng, Zexian
  • Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America.
Jiang, Xia
  • Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America.
Li, Xiaoyu
  • Department of Social and Behavioral Sciences, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America.
Wells, Alan
  • Department of Pathology, University of Pittsburgh and Pittsburgh VA Health System, Pittsburgh, Pennsylvania, United States of America.
Luo, Yuan
  • Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America.
Neapolitan, Richard
  • Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America.

MeSH Terms

  • Breast Neoplasms / chemically induced
  • Breast Neoplasms / epidemiology
  • Estrogen Replacement Therapy
  • Estrogens, Conjugated (USP) / adverse effects
  • Estrogens, Conjugated (USP) / therapeutic use
  • Female
  • Humans
  • Medroxyprogesterone / adverse effects
  • Medroxyprogesterone / therapeutic use
  • Menopause / drug effects
  • Middle Aged

Grant Funding

  • R01 LM011663 / NLM NIH HHS
  • R01 LM011962 / NLM NIH HHS
  • R01LM011663 / NIH HHS
  • R01LM011962 / NIH HHS

Conflict of Interest Statement

The authors have declared that no competing interests exist.

References

This article includes 17 references
  1. Avis NE, Crawford SL, Greendale G, Bromberger JT, Everson-Rose SA, Gold EB, Hess R, Joffe H, Kravitz HM, Tepper PG, Thurston RC. Duration of menopausal vasomotor symptoms over the menopause transition.. JAMA Intern Med 2015 Apr;175(4):531-9.
  2. Stuenkel CA, Davis SR, Gompel A, Lumsden MA, Murad MH, Pinkerton JV, Santen RJ. Treatment of Symptoms of the Menopause: An Endocrine Society Clinical Practice Guideline.. J Clin Endocrinol Metab 2015 Nov;100(11):3975-4011.
    pubmed: 26444994doi: 10.1210/jc.2015-2236google scholar: lookup
  3. Pinkerton JAV, Aguirre FS, Blake J, Cosman F, Hodis H, Hoffstetter S. The 2017 hormone therapy position statement of the North American Menopause Society. Menopause 2017;24(7):728–53.
    doi: 10.1097/GME.0000000000000921pubmed: 0google scholar: lookup
  4. Sood R, Faubion SS, Kuhle CL, Thielen JM, Shuster LT. Prescribing menopausal hormone therapy: an evidence-based approach.. Int J Womens Health 2014;6:47-57.
    doi: 10.2147/IJWH.S38342pmc: PMC3897322pubmed: 24474847google scholar: lookup
  5. Anderson GL, Limacher M, Assaf AR, Bassford T, Beresford SA, Black H, Bonds D, Brunner R, Brzyski R, Caan B, Chlebowski R, Curb D, Gass M, Hays J, Heiss G, Hendrix S, Howard BV, Hsia J, Hubbell A, Jackson R, Johnson KC, Judd H, Kotchen JM, Kuller L, LaCroix AZ, Lane D, Langer RD, Lasser N, Lewis CE, Manson J, Margolis K, Ockene J, O'Sullivan MJ, Phillips L, Prentice RL, Ritenbaugh C, Robbins J, Rossouw JE, Sarto G, Stefanick ML, Van Horn L, Wactawski-Wende J, Wallace R, Wassertheil-Smoller S. Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: the Women's Health Initiative randomized controlled trial.. JAMA 2004 Apr 14;291(14):1701-12.
    doi: 10.1001/jama.291.14.1701pubmed: 15082697google scholar: lookup
  6. . Design of the Women's Health Initiative clinical trial and observational study. The Women's Health Initiative Study Group.. Control Clin Trials 1998 Feb;19(1):61-109.
    pubmed: 9492970doi: 10.1016/s0197-2456(97)00078-0google scholar: lookup
  7. LaCroix AZ, Chlebowski RT, Manson JE, Aragaki AK, Johnson KC, Martin L, Margolis KL, Stefanick ML, Brzyski R, Curb JD, Howard BV, Lewis CE, Wactawski-Wende J. Health outcomes after stopping conjugated equine estrogens among postmenopausal women with prior hysterectomy: a randomized controlled trial.. JAMA 2011 Apr 6;305(13):1305-14.
    doi: 10.1001/jama.2011.382pmc: PMC3656722pubmed: 21467283google scholar: lookup
  8. Anderson GL, Chlebowski RT, Aragaki AK, Kuller LH, Manson JE, Gass M, Bluhm E, Connelly S, Hubbell FA, Lane D, Martin L, Ockene J, Rohan T, Schenken R, Wactawski-Wende J. Conjugated equine oestrogen and breast cancer incidence and mortality in postmenopausal women with hysterectomy: extended follow-up of the Women's Health Initiative randomised placebo-controlled trial.. Lancet Oncol 2012 May;13(5):476-86.
  9. Chlebowski RT, Anderson GL, Gass M, Lane DS, Aragaki AK, Kuller LH, Manson JE, Stefanick ML, Ockene J, Sarto GE, Johnson KC, Wactawski-Wende J, Ravdin PM, Schenken R, Hendrix SL, Rajkovic A, Rohan TE, Yasmeen S, Prentice RL. Estrogen plus progestin and breast cancer incidence and mortality in postmenopausal women.. JAMA 2010 Oct 20;304(15):1684-92.
    doi: 10.1001/jama.2010.1500pmc: PMC5142300pubmed: 20959578google scholar: lookup
  10. Beral V. Breast cancer and hormone-replacement therapy in the Million Women Study.. Lancet 2003 Aug 9;362(9382):419-27.
    pubmed: 12927427doi: 10.1016/s0140-6736(03)14065-2google scholar: lookup
  11. . Breast cancer and hormone replacement therapy: collaborative reanalysis of data from 51 epidemiological studies of 52,705 women with breast cancer and 108,411 women without breast cancer. Collaborative Group on Hormonal Factors in Breast Cancer.. Lancet 1997 Oct 11;350(9084):1047-59.
    pubmed: 10213546
  12. Lyytinen H, Pukkala E, Ylikorkala O. Breast cancer risk in postmenopausal women using estrogen-only therapy.. Obstet Gynecol 2006 Dec;108(6):1354-60.
  13. Lyytinen H, Pukkala E, Ylikorkala O. Breast cancer risk in postmenopausal women using estradiol-progestogen therapy.. Obstet Gynecol 2009 Jan;113(1):65-73.
    pubmed: 19104361doi: 10.1097/aog.0b013e31818e8cd6google scholar: lookup
  14. Fournier A, Berrino F, Riboli E, Avenel V, Clavel-Chapelon F. Breast cancer risk in relation to different types of hormone replacement therapy in the E3N-EPIC cohort.. Int J Cancer 2005 Apr 10;114(3):448-54.
    doi: 10.1002/ijc.20710pubmed: 15551359google scholar: lookup
  15. Hersh AL, Stefanick ML, Stafford RS. National use of postmenopausal hormone therapy: annual trends and response to recent evidence.. JAMA 2004 Jan 7;291(1):47-53.
    doi: 10.1001/jama.291.1.47pubmed: 14709575google scholar: lookup
  16. Files JA, Ko MG, Pruthi S. Bioidentical hormone therapy.. Mayo Clin Proc 2011 Jul;86(7):673-80, quiz 680.
    doi: 10.4065/mcp.2010.0714pmc: PMC3127562pubmed: 21531972google scholar: lookup
  17. Santen RJ, Allred DC, Ardoin SP, Archer DF, Boyd N, Braunstein GD, Burger HG, Colditz GA, Davis SR, Gambacciani M, Gower BA, Henderson VW, Jarjour WN, Karas RH, Kleerekoper M, Lobo RA, Manson JE, Marsden J, Martin KA, Martin L, Pinkerton JV, Rubinow DR, Teede H, Thiboutot DM, Utian WH. Postmenopausal hormone therapy: an Endocrine Society scientific statement.. J Clin Endocrinol Metab 2010 Jul;95(7 Suppl 1):s1-s66.
    pmc: PMC6287288pubmed: 20566620doi: 10.1210/jc.2009-2509google scholar: lookup

Citations

This article has been cited 2 times.
  1. Hasan M, Browne E, Guarinoni L, Darveau T, Hilton K, Witt-Enderby PA. Novel Melatonin, Estrogen, and Progesterone Hormone Therapy Demonstrates Anti-Cancer Actions in MCF-7 and MDA-MB-231 Breast Cancer Cells.. Breast Cancer (Auckl) 2020;14:1178223420924634.
    doi: 10.1177/1178223420924634pubmed: 32636633google scholar: lookup
  2. Zeng Z, Espino S, Roy A, Li X, Khan SA, Clare SE, Jiang X, Neapolitan R, Luo Y. Using natural language processing and machine learning to identify breast cancer local recurrence.. BMC Bioinformatics 2018 Dec 28;19(Suppl 17):498.
    doi: 10.1186/s12859-018-2466-xpubmed: 30591037google scholar: lookup