Breast Cancer Risk Factor Drops with Decline in HRT
A decline in hormone replacement therapy may be causing a decrease in the rates of a known risk factor for breast cancer, according to researchers.
A recent study published in the November issue of Cancer Epidemiology, Biomarkers & Prevention has shown that the rate of a benign breast condition known as atypical ductal hyperplasia has decreased along with the decline in hormone replacement therapy (HRT) seen since 2002. Atypical ductal hyperplasia is a known risk factor for developing breast cancer, and is suspected of being a breast cancer precursor. According to researchers, women diagnosed with atypical ductal hyperplasia have a 3 to 5 times higher rate of developing breast cancer in either breast.
In this study, researchers compared the atypical ductal hyperplasia rate in 1999 and 2005, and found that it decreased from 5.5 per 10,000 mammograms to 2.4 per 10,000 mammograms. Over the same time period, the rate of mammography increased, and the rate of HRT use decreased from 35 percent to 11 percent.
The debate over a link between the use of combined estrogen and progestin hormone replacement therapy (HRT) for menopause and breast cancer has been raging ever since the Womenâ€™s Health Initiative (WHI) Hormone Program showed an increase in breast cancer in women taking Prempro in 2002. The study was halted early in July 2002 when the increased breast cancer risk was detected. As a result, there has been a a huge decline in women taking combined estrogen/progestin HRT.
Quite quickly after the drop in HRT use began, researchers also began seeing a drop in breast cancer cases. The decrease in atypical ductal hyperplasia seen in this more recent research may shed light on exactly how HRT causes the development of breast cancer. Of course, the results of this study are not strong enough on their own to prove that a decline in atypical ductal hyperplasia was caused by a decline in HRT, but the correlation is striking.
Along with the release of this research, combined estrogen/progestin HRT took another hit in November when a jury found that Pfizer, manufacturer of the HRT drugs Prempro and Provera, must pay an Illinois woman at least $6.3 million in damages because of their drugs' connection with her breast cancer. Pfizer recently acquired Wyeth, the maker of Prempro. Wyeth had previously lost 6 of 9 lawsuits related to Prempro and breast cancer.
The increasing evidence linking certain forms of HRT to breast cancer has caused some women to look to alternative treatments like herbs and bioidentical hormones. However, the National Cancer Institute and other researchers stress that there is little to no evidence that these alternative treatments are safe either. While the WHI study linked breast cancer to progestin (a synthetic progesterone), the study did not look at the use of natural progesterone to show if it was as safe or safer than skipping hormonal therapy for menopause altogether.
Authour: Kristies McNealy M.D.
Kristie McNealy M.D.is a medical doctor turned freelance writer and medical blogger. You can find her blogging about women's and children's health at www.KristieMcNealy.com
Menes TS, Kerlikowske K, Jaffer S, Seger D, Miglioretti DL. Rates of Atypical Ductal Hyperplasia Have Declined with Less Use of Postmenopausal Hormone Treatment: Findings from the Breast Cancer Surveillance Consortium. Cancer Epidemiol Biomarkers Prev November 2009 18:2822-2828; doi:10.1158/1055-9965.EPI-09-0745.
Rossouw JE, Anderson GL, Prentice RL, et al. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: Principal results from the Womenâ€™s Health Initiative randomized controlled trial. JAMA 2002; 288(3):321â€“333.