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Contradictory Reports On Hormone Replacement Therapy and Breast Cancer Risk Alarm Women (dateline June 13, 2000)


The recent media attention devoted to conflicting studies on hormone replacement therapy (HRT) and breast cancer risk are causing fear among many menopausal and post-menopausal women who are on HRT or considering the therapy.  According to women’s health experts at the annual meeting of the Congress on Women’s Health and Gender-Based Medicine, contradictory news reports are causing some women to avoid HRT or stop taking it unnecessarily. 

Recently, women have been overwhelmed with reports that HRT may increase the risk for breast cancer.  One particular study of 46,355 women in the Breast Cancer Detection Demonstration Project , a national breast cancer screening program, found almost a 9% increase in breast cancer risk among women who used combined HRT (estrogen and progestin) each year.

However, Dr. Judith Reichman, a professor at the University of California, Los Angeles who spoke at the Congress on Women’s Health and Gender-Based Medicine meeting, said that the results of the Breast Cancer Detection Demonstration Project are often misinterpreted.  Some women may incorrectly assume that a 9% increase in breast cancer risk each year would mean that in 10 years, a woman’s risk of breast cancer would be 90%.  In reality, the researchers noted a 9% increase in the incidence of breast cancer among the group of women on combined HRT when they studied health reports of all the women in the study each year. 

“We have to take each study and apply it to each patient,” said Dr. Reichman.  Some studies show that HRT may increase the risk of breast cancer for some women, especially if it is taken for more than five years.  Each woman and her physician need to take into account the benefits and risks of HRT, and then make an informed decision as to whether or not to take HRT.  HRT has been shown to help protect against osteoporosis, a degenerative bone disease, and may provide some benefits against heart disease , Alzheimer’s diseases , Type II diabetes , and more. 

Women health experts blame the media for emphasizing the negative findings of HRT studies while devoting little attention to studies that do not find a relationship between HRT and breast cancer risk.  Two large studies conducted by the American Cancer Society and the Iowa’s Women’s Health Study did not find an increased breast cancer risk with HRT, but these studies were not well reported to the public. 

In a study published in the March 15, 1999 issue of the medical journal Cancer, 9,494 women with benign (non-cancerous) breast diseases (such as fibroadenoma) who took HRT were found to be at the same risk of developing breast cancer as women with benign breast diseases who did not take HRT.  Lead researcher David Page, MD of Vanderbilt University, said that women need to know that the risk of breast cancer for low-dose ERT (HRT with estrogen alone) is minimal, and that there are many benefits to HRT.  Dr. Page emphasizes what most physicians do, that the decision to use HRT or not should be an informed one and not one made out of fear.  

Another problem with the negative media attention aimed at HRT is that women go to their physicians with misinterpreted news reports that say HRT definitely increases breast cancer risk, making the physicians appear as though they are uninformed.  “What we’re facing now is a huge credibility gap,” Dr. Reichman told women’s health experts.   

Studies Cite Fear of Breast Cancer As Women’s Main Objection to HRT

In a German study published in the November 1999 issue of the Maturitas medical journal, researchers concluded that “fear of cancer is one of the main reasons why women object to hormone replacement therapy (HRT).” The researchers suggest that “physicians must be able to counteract this fear with fact, and counsel patients on their individual risk, as well as putting any cancer risk into perspective with other long-term benefits.”

At the annual meeting of the Congress on Women’s Health and Gender-Based Medicine, Dr. Reichman said that only around 30% of women will still be taking HRT one year after starting it, largely due to the fact that women are afraid of developing breast cancer or do not want to experience vaginal bleeding after menopause.

At the third annual Duke Conference on Women’s Health in Chapel Hill, North Carolina in April 2000, Diana L. Dell, MD also cited the top two reasons why women stop taking HRT to be:

  1. The news media’s portrayal that HRT causes breast cancer
  2. Vaginal bleeding

    3. At the Duke conference, Dr. Dell said that ERT (HRT with estrogen alone) may help improve mood and depression, enhance short term and long term memory, and could possibly help with Alzheimer’s disease.  Dr. Dell estimates that between 10% and 15% of eligible women use HRT.  Interestingly, according to Dr. Dell, “the majority of women who take HRT are physicians or wives of physicians.”

    In another study published in the August 1997 issue of the Journal of Women’s Health, researchers interviewed 1082 American women between the ages of 50 and 80 to find out their perceptions of HRT.  Approximately 43% of the women were on HRT, 21% had used HRT in the past, and 36% had never used HRT.  In the study, the most frequently cited reasons for discontinuing HRT were:

  3. Side effects (26.6%)
  4. Physician’s advice (22.9%)
  5. Fear of cancer (15.4%)
  6. Not wanting menstrual periods or bleeding (15.2%)

    7. Of past HRT users, over half said that they stopped taking HRT on their own volition and not from the advice of their physicians.  Current HRT users cited the relief of menopausal symptoms (such as hot flashes and vaginal dryness), osteoporosis prevention, and physicians’ advice as the top three reasons for taking HRT.   

    It is estimated that 8.6 million American women take combined HRT (estrogen and progestin) according to Wyeth-Ayerst Laboratories, a drug company that makes Premarin, a type of synthetic estrogen.  Another 12 million women who have had hysterectomies (removal of the uterus) take estrogen alone.

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