Hormone-replacement therapy and breast cancer
May 26, 1999
Web posted at: 10:04 AM EDT (1404 GMT)
By Marie Stone
One of the more nerve-racking, complicated and personal questions for menopausal women who either have a history of breast cancer or are at high risk for developing the disease is whether or not to take hormone replacement therapy (HRT). Some studies have shown that long-term HRT use may further increase a woman's risk of breast cancer.
This April, Dr. Leon Speroff, professor of obstetrics and gynecology at Oregon Health Sciences University (OHSU) School of Medicine, offered his insights on the HRT question. He presented his ideas on the risks and benefits of HRT during the Fourth Annual OHSU Women's Health Conference in Portland, Oregon.
The health benefits
The list of potential health benefits of HRT is impressive. HRT offers protection against heart disease, the number-one killer of women in the United States today. In addition, HRT helps keep bones healthy, offering protection against osteoporosis and related bone fractures. Studies have shown that women who take HRT may realize the following benefits:
A decreased risk of Alzheimer's disease, colorectal cancer and cataracts
Less of a need for false teeth
Less severe osteoarthritis
The potential health risk
The major controversy is HRT's association with an increased risk of breast cancer, Speroff noted.
"We have over 50 studies, and there is no clear-cut answer," Speroff said. "We have positive studies. We have negative studies. I think the state of the art was beautifully illustrated in 1995 when we had reports from (two) respected teams of epidemiologists with opposite conclusions, two weeks apart."
In the summer of 1995 researchers of the Nurses' Health Study concluded in The New England Journal of Medicine that five-or-more years of hormone replacement therapy was associated with a 46-percent increased risk of breast cancer.
Two weeks later researchers at Fred Hutchinson Cancer Research Center and the University of Washington in Seattle conveyed opposite results in The Journal of the American Medical Association, "On the whole, the use of estrogen with progestin HRT does not appear to be associated with an increased risk of breast cancer in middle-aged women."
Uniformity, agreement and consistency
"We all believe that oral contraceptives protect against ovarian cancer," Speroff said. "Most of us believe that estrogen protects against coronary heart disease. We all believe that smoking causes lung cancer."
"Why do I believe it? Because every study says the same thing," Speroff said. When studies have uniformity, agreement and consistency, the cause-and-effect relationship is clearer.
"With breast cancer and hormone replacement therapy, we have the opposite," Speroff said. "We have lack of agreement, lack of uniformity, lack of consistency. That tells me that if hormone therapy has an effect on breast cancer, it has to be a small (one). If it were a major effect, a large effect, we would have agreement."
Speroff noted that some agreement in these studies does exist: all of them have failed to show an increased risk of breast cancer in women who are on HRT for less than five years.
Answering the HRT question
"We have a growing number of breast-cancer survivors who face a very difficult decision about whether or not to use HRT," Speroff said. He added that it is very unlikely that significant new data will surface in the next ten years to make their decision notably easier.
In the future, Speroff said, we can look forward to the conclusions of two large, randomized clinical trials: The Women's Health Initiative, a U.S. study that will continue until 2008, and the larger Wisdom Study from the United Kingdom, scheduled to produce results in 2011.
Speroff displayed a slide to the audience members, a portion of whom were health professionals. The message on the slide read, "Until data are available from randomized clinical trials, the patient's decision is the right decision -- support it."
"In my opinion, in the absence of studies, in the absence of data, there is no right or wrong answer," Speroff said.
To the women facing this decision, Speroff offered these words of wisdom: "I would urge you to consider the decision as short-term. Make a decision today. A year from now, reconsider it. Review it. Evaluate all the new information, and make another short-term decision. This is a very active, aggressive process, and this is the kind of process that you and your clinician should have on a year-to-year basis."
Copyright 1999 by WebMD, Inc. All rights reserved.
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