While hormone therapy is associated with increased breast cancer risk, a new approach could bring women relief from hot flashes and mood swings without added risk.
A combination of estrogen and a selective estrogen receptor modulator (SERM) — which blocks estrogen from affecting certain types of tissue — could alleviate the symptoms of menopause without increasing the risk of breast or uterine cancer, Yale researchers found in a recent study. Yale School of Medicine professor Hugh Taylor and Brazilian researcher Jaime Kulak examined various types of SERMs to find which combinations could best prevent the negative effects of hormone therapy.
Kulak presented their findings at the American Society for Reproductive Medicine conference in Atlanta last week.
Since a 2002 study by the National Institutes of Health showed that hormone therapy increased the risk of breast cancer and other illnesses, hormone therapy has dipped in popularity, Taylor said. When women enter menopause, their ovaries produce dramatically less estrogen, causing hot flashes, trouble sleeping and mood problems. While estrogen supplements alleviate many of these symptoms, estrogen increases the risk of uterine cancer in women who have not had their uteruses removed. Although doctors prescribe another hormone, progestin, to counteract this increased risk, progestin raises the risk of breast cancer.
The risks associated with hormone therapy, Taylor said, led his team to seek a substitute for progestin which could curb the negative effects of estrogen without increasing the risk of breast cancer.
“How do you give women the benefits of estrogen without the risks that come with progestin?” Taylor said.
Taylor and Kulak found that adding SERMs to estrogen therapy slowed cell growth in breast tissue. By slowing cell growth, SERMs lowered the risk of cancer.
Pharmaceutical companies such as Wyeth (which was bought by Pfizer on Oct. 15) are already running clinical trials combining estrogen and SERMs for hormone therapy, Taylor said. A Food and Drug Administration-approved treatment could be on the market in a few years, he added.
“I think it will be the standard for hormone therapy,” Taylor said. “Right now a woman has a choice between relief of symptoms or suffering, but with relief comes a terrible risk. It’s a way to give women the best of both worlds.”
Yale researcher Lubna Pal said Taylor and Kulak’s study was well-designed, but cautioned that further investigation is necessary.
“The adverse effects of estrogen will be taken care of — that’s the promise of this combination,” Pal said. “[But] how far are we from this promise? I think pretty far off.”
Pal noted that both estrogen and SERMs increase the risk of blood clots. Before this combination is approved by the FDA, Pal said, researchers will need to ensure that combining estrogen and SERMs will not lead to higher incidences of stroke and heart attack.
The study was funded in part by Wyeth’s Women’s Health Research Institute, a research arm of the company dedicated to women’s health issues.