Hormone Replacement Therapy ("HRT") places women at a higher risk for breast cancer, ovarian cancer, lupus, heart attack, stroke, gall bladder cancer, asthma, and other serious illnesses, according to recent studies. If you have develped any of these serious illnesses, please call our lawyers or e-mail our law firm by submitting a Potential Case Form to learn more about your legal rights concerning HRT. Prempro, Premarin, Provera, Premphase, Estradiol, and Medroxyprogesterone are commonly prescribed hormone replacement drugs.
If you or a loved one has been diagnosed with breast cancer, ovarian cancer, or with any other female cancer, and if you have ever regularly used hormone replacement drugs for menopause, there is a good chance that the hormones fed your cancer. We thought you might be interested in some of the recent studies. Breast Cancer Breast cancer is not a single disease.
There are many different kinds of breast tumors. Hormone therapy has been associated with two types in particular: invasive (or infiltrating) lobular cancer, and estrogen receptor positive invasive ductal cancer. The Women's Health Initiative Trial was halted in July 2002 because, among other reasons, Prempro was causing an unacceptable increase in breast cancer.
Since then, there have been six major studies on the risk of breast cancer from hormone therapy on a total of more than 11,200 women with breast cancer. They have all found that combination hormone therapy is strongly associated with two particular types of breast cancer. What follows is a brief summary of these six studies. 1. Tjonneland et al., "HRT in Relation to Breast Carcinoma Incidence Rate Ratios", Cancer (June 1, 2004) 100(11), 2329-37. Women on hormone therapy developed more than twice as many ductal breast cancers and almost four times as many lobular breast cancers as women not taking those drugs. In this large prospective case control study in Denmark, funded by the Danish Cancer Institute, 29,000 women were followed for six years. 2. Holmberg et al., "HABITS (HRT after breast cancer---is it safe?), a randomised comparison: trial stopped", Lancet, Feb 3 2004 363:453-455.
This was a randomized trial in Sweden to see if breast cancer survivors could safely use hormone therapy. The trial was halted halfway through it because the women on hormones were getting almost three times as much of breast cancer recurrence as the placebo group not on the hormones. It found almost a five-fold increased risk of hormone receptor positive breast cancers. 3. Stahlberg et al., "Increased Risk of Breast Cancer Following Different Regimens of HRT Frequently Used in Europe", Int J Cancer 109, 721-27 (2004).
This is a study of breast cancer in Danish nurses, followed over time. Women taking combination hormone therapy (an estrogen plus a progestin) developed three times as much breast cancer as the other groups. 4. Verkoouen et al., "Important Increase of lobular breast cancer incidence in Geneva Switzerland", Int. J. Cancer, 104, 778-81 (2003). The rates of different types of breast cancer were tracked over 25 years in Geneva, where both the rate of breast cancer and the use of hormone therapy in menopause are the highest in the world.
The study found a dramatic seven-fold increase in the amount of invasive lobular breast cancer in the women with the highest use of hormone drugs. 5. Million Women Study Collaborators, "Breast Cancer and hrt in the Million Women Study", Lancent Aug 9 2003, 362, pp 419-427. This is by far the largest study of women with breast cancer and hormone therapy. See their website, http://www.millionwomenstudy.org.uk. Funded by the British government, the investigators are following over 1,300,000 post-menopausal women in the UK for years to come. In the first but not last report on breast cancer, they found after only a two and a half year average follow-up that twice as many women on combination therapy were getting breast cancer, without distinguishing between different types of tumors (that project is underway and will be published in a year or so).
The study investigators estimated that hormone therapy had caused over 20,000 excess cases if breast cancer in the UK alone, and just in women 50-65 in the last ten years. 6. Li, et al. "Relationship Between Long Durations and Different Regimens of HT and Risk of Breast Cancer," JAMA, 289(24), 3254-63.
This is a large case control study funded by the US National Cancer Institute that focused on women in the Seattle area. In 975 women with breast cancer, they found that the risk was tripled for lobular breast cancer and doubled for estrogen positive and progesterone positive tumors of all types in women who had ever used combination hormone therapy in menopause.
Ovarian Cancer As for ovarian cancer, there have been several large studies published in the last few years that confirm a causal association between hormone therapy and ovarian cancer, especially in long time users of estrogen only, and especially for some types of ovarian cancer tumors and not for others. Just like breast cancer, ovarian cancer is not just one disease, but a name for a widely different group of tumors that all happen to grow in the ovaries. The three largest studies published to date are as follows: 1.
The largest single study is from Australia: Purdie et al.:"Hormone replacement therapy and risk of epithelial ovarian cancer", Br. J. of Cancer (1999)81(3), 559-563. In this study on 973 women with ovarian cancer, they found that unopposed estrogen hormone therapy was associated with a significant increase in risk of endometrioid or clear cell epithelial ovarian tumors (OR=2.56, upper confid. interval 4.94) in all women.
But in women without a hysterectomy, that is, in women who still had their uterus, and who also did not have a tubal ligation, then all forms of ovarian cancer were increased significantly; such women on estrogen only therapy were four times as likely to develop ovarian cancer as never users. The risk went up steadily with length of use of the hormone drugs. 2. The second largest case control study, with 655 cases of invasive ovarian cancer, is from Sweden. See Riman et al., “Hormone replacement therapy and the risk of invasive epithelial ovarian cancer in Swedish women”, J Natl Cancer Inst 2002;94:467-504.
This study also found a statistically significant increase in ovarian cancers, sometimes a tripling of the risk, especially of the tumor types endometrioid and mucinous, in women on most forms of hormone therapy. 3. The third recent big case control study was done by the National Cancer Institute. Lacey et al., "Menopausal HRT and Risk of Ovarian Cancer", JAMA, July 17, 2002, 288(3), 334-341. This study looked at 329 ovarian cancer cases at 29 sites across the United States.
This study mostly confirmed the Australian study: they found the risk to be mostly with estrogen-only hormone drugs; that the rate of increased risk varied by type of ovarian tumor; and that women without hysterectomies were at a much higher risk of a hormone drug induced tumor. They also found that the risk increased with the length of use of the hormone drugs.
The risk was tripled for women on estrogen for over twenty years. The Million Women Study has not reported any data on ovarian cancer yet. The Women's Health Initiative combination therapy trial found an elevation in risk, but it was not statistically significant (the study is much smaller than the three described above; it had only 32 women with ovarian cancer, and they were followed for only 5 years, so there was not the time nor the numbers to see the effects on tumor types and duration seen in the larger studies.).
See Anderson et al., "Effects of Estrogen Plus Progestin on Gynecologic Cancers and Associated Diagnostic Procedures", JAMA, Oct 1, 2003 290(13), 1739-1748. The WHI estrogen only arm has not published any data on ovarian cancer. However, since all the women in that study had hysterectomies, and the study followed them for only about 7 years, and because it is too small to see increases in rare cancers, it is not likely to provide any information that would change the picture given by the three major case control studies described above.
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