Since more women with breast cancer are surviving into their menopausal years, management of menopausal symptoms has become increasingly important for breast cancer survivors. There is no doubt HRT is effective in treating menopausal symptoms, but considering recent evidence linking HRT to increased risks for breast cancer, heart disease , stroke , blood clots , and dementia , is it a safe option for breast cancer survivors?

On December 17, 2003, the Hormonal Replacement Therapy After Breast Cancer Diagnosis—Is It Safe? (HABITS) trial was stopped three years early because researchers found that HRT significantly increased the risk of cancer recurrence in breast cancer survivors. The results of this study were published in the February 7, 2004 issue of The Lancet .

About the Study

This study included 345 women who had completed breast cancer treatment and were free from recurrence when the study began. The women had menopausal symptoms severe enough to consider treatment, but were otherwise healthy.

The women were randomized to receive either HRT or treatment without hormones for two years. They saw a breast cancer specialist at least twice yearly and received mammograms every 1–2 years.

The Findings

The HABITS trial, which started in 1997, was originally planned to include as many as 1,300 women who would be followed up for five years. But after an average follow-up period of only 2.1 years, the data monitoring committee determined that the risks of taking HRT outweighed the benefits for breast cancer survivors, so the study was halted.

Over the course of the study, 26 women in the HRT group developed breast cancer, compared with seven women in the non-HRT group. Furthermore, eight women reported serious adverse events in the HRT group, compared to four in the non-HRT group.

Even though these findings were compelling enough to prematurely halt the study, they do have certain limitations. First, the researchers didn’t collect data on menopausal symptoms or quality of life, so they can’t say whether HRT actually helped these women. Also, since the trial did not include the planned 1,300 women and five years of followup, the results might have been different if the trial had gone on as planned.

How Does This Affect You?

Although this is just one small study, its findings are considerably strengthened when viewed in the context of other research questioning the long-term safety of HRT. All evidence considered, HRT is probably not in the best interest of most women. This is particularly true for breast cancer survivors, whose risk of another breast cancer is already higher than average.

If you are taking HRT to relieve menopausal symptoms or decrease your risk of bone fractures, do not stop taking as soon as you finish reading this article. Schedule a time to talk with your physician about the benefits and risks of continuing your treatment. Considering the available evidence, physicians should carefully consider the risks associated with HRT before prescribing it to postmenopausal women—especially those who have had breast cancer or who have an elevated risk for breast cancer, heart disease, stroke, blood clots, and dementia.

How can you safely manage menopausal symptoms? First, you should evaluate your symptoms and decide if treatment is really necessary. For some women, menopausal symptoms are more of an uncomfortable inconvenience than a medical condition. But if your symptoms are debilitating enough to disrupt your everyday life, talk to your doctor; there are less risky options for managing menopause. And the mounting evidence regarding the risks of HRT will certainly fuel major efforts to develop other safe alternatives in the near future.