Ask an Expert: HRT for breast cancer survivors

Q. I am a breast cancer survivor. Is it safe for me to take hormone replacement therapy (HRT)?

Answer from the expert staff of breast cancer research at the Robert W. Franz Cancer Research Center at Providence Portland Medical Center: That’s a topic of hot debate. Five years ago, we firmly believed that the benefits of HRT for most menopausal women greatly outweighed the risks. In addition to alleviating symptoms of menopause, we believed that HRT strengthened bones, decreased the risk of heart attack, and decreased the risk of Alzheimer’s disease.

But several studies in the last couple of years have shown that HRT does not affect the heart as we originally believed it would. Evidence from the Women’s Health Initiative (WHI) study, which researched the effects of a combined estrogen-progestin medication called Prempo in more than 16,000 postmenopausal women, showed that HRT actually increases the risk of heart attacks, strokes and blood clots.

The WHI study also found that women taking Prempro were at increased risk of breast cancer. In July 2002, the WHI determined that risks associated with Prempro outweighed potential benefits, and halted the Prempro arm of the study three and a half years early.

In May 2003, findings were published from a WHI sub-study called the Women’s Health Initiative Memory Study (WHIMS). Although HRT had long been believed to help reduce the risk of cognitive disorders, WHIMS results indicated that HRT actually increased the risk of dementia, including Alzheimer’s disease. Today it looks like HRT is best for protecting bones, but not effective at preventing other serious conditions.

There are other options for treating menopausal side effects. In terms of dealing with hot flashes, there’s an effective new treatment option that’s safe for breast cancer survivors. It’s called venlafaxine (Effexor), and it is actually an antidepressant, but it promotes activity in the brain that reduces hot flashes. There are also effective drugs for reducing the risk of osteoporosis, such as alendronate (Fosamax). Vaginal dryness can be treated well with Estring, a ring that is placed high in the vagina and releases estrogen slowly into the surrounding tissues. Talk to your doctor about therapies that might be right for you.

All of this is not to say that we don’t ever consider hormone therapy for breast cancer survivors. In the WHI study, women taking estrogen alone did not have the same increased risk of breast cancer as the women taking combined estrogen and progestin. That part of the WHI study is ongoing. Long-term exposure to estrogen alone may increase your risk of endometrial cancer, but if you have had a hysterectomy and are primarily interested in therapy that helps manage hot flashes, estrogen may be an option.

Last updated: July 2003

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