SUNDAY, April 1 (HealthDay News) -- Several weeks after a study
suggested that women who take estrogen-only hormone replacement to
treat menopause symptoms may be at lower risk for developing breast
cancer, another, much-larger study finds that when used for longer
than 10 years, estrogen-only regimens actually raise a woman's
long-term risk for breast cancer.
The new study was funded by the National Cancer Institute, part
of the U.S. National Institutes of Health, whereas the previous one
was partially funded by drug manufacturer Wyeth.
Researchers evaluated follow-up data from the Nurse's Health
Study collected from 1980 through 2008. The women in the study were
30 to 55 years old in 1976. Overall, the risk for breast cancer was
88 percent higher among women who had taken estrogen plus
progesterone for 10 to 14.9 years, compared to women who did not.
This risk more than doubled for women who used
estrogen-plus-progesterone therapy for 15 to 19.9 years.
Women who used estrogen-only therapy after menopause had 22
percent increased risk for breast cancer if they used it for 10 to
14.9 years, and 43 percent greater risk if they used it longer than
There was no increased risk seen among women who took estrogen
for fewer than 10 years. Women did not have an increased risk of
dying from breast cancer, the study showed.
Hormone replacement therapy (HRT) fell from grace after the U.S.
Women's Health Initiative study was stopped early in 2002 because
HRT was shown to increase the risk of strokes and breast and
ovarian cancer. Some subtleties have emerged since that time. For
example, short-term use of HRT is now deemed fairly safe for some
women who have severe menopausal symptoms. Estrogen-only therapy is
reserved for women who have had a hysterectomy; women with an
intact uterus who use HRT must take the hormone progestin
(synthetic progesterone) with estrogen to prevent uterine
"For combination therapy there is so much data about the dangers that we really tell people that if they must take it to treat symptoms, they should only do so for a year or two at most," said study author Dr. Wendy Chen, an associate physician at Brigham and Women's Hospital and an assistant professor in medicine at the Breast Cancer Treatment Center at the Dana-Farber Cancer Institute in Boston. "For estrogen alone, there is more safety data for someone who wants to take it for five or six years."
Chen is scheduled to present her findings at this week's annual
meeting of the American Association for Cancer Research in
Her advice is for women to think about why they are taking
supplemental hormones. "If it is for hot flashes, they don't last
forever," she said. If vaginal dryness is the issue, there are
vaginal hormone preparations. "You are not going to have the
systemic effects that you will from talking a pill," she said.
Dr. Larry Norton, deputy physician-in-chief for breast cancer
programs at Memorial Sloan-Kettering Cancer Center and medical
director of the Evelyn H. Lauder Breast Center, in New York City,
does not recommend that women take estrogen after menopause.
"The jury is still out on how safe estrogen alone is, but I am not recommending it, and the major reason why is because every drug I know that reduces the risk of breast cancer reduces estrogen," he said. "Saying an estrogen is going to be safe raises an important question mark in my mind," Norton said. "Alternative treatments may help treat the symptoms and risks associated with menopause, so why take the chance?"
Because the new study was presented at a medical meeting, the
data and conclusions should be viewed as preliminary until
published in a peer-reviewed journal.
Learn more about the
benefits and risks of HRT through the North
American Menopause Society.
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
Copyright © EBSCO Publishing. All rights reserved.