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New Breast Cancer Risk Found With Hormone Replacement Therapy


"The commonly held belief that aging routinely requires pharmacological management has unfortunately led to neglect of diet and lifestyle as the primary means to achieve healthy aging," they write. "Now is an appropriate time to reassess this emphasis."

Cosman says the decision to stop -- or start HRT -- isn't easy. "I have to tell you that I have patients who've been on long term estrogens who don't want to change. They think they look better, they feel better, the skin is better, the hair is better. Although this isn't true disease prevention, it probably is a quality of life issue that has to be considered with some women."

Eugenia Calle, PhD, director of analytical epidemiology at the American Cancer Society, reviewed the study for WebMD and says it appears that the risk of breast cancer with HRT with progestin is greater than first believed. But she adds that the findings are not surprising. "It really does look like from these data that if women continue to use these combination products for a longer period of time, the risks may turn out to be moderate and less modest," says Calle. "We've been heading in this direction, and we've known of the association between breast cancer and combination therapy ... that is not brand new, it's what we suspected. The main contribution of this study is it gives us a more precise amount of risk that a woman may incur if they use the combination product for a number of years."

But she adds, "This is one study and there will be others looking that this." The risk should also be put in perspective. Calle notes, for example, that people who smoke are 20 to 25 times more likely to develop lung cancer than are nonsmokers, while women on the combination HRT product were less than two times as likely to develop breast cancer than were estrogen-alone users and women who have never used estrogen products.

Vital Information:


  • An estimated 20% of women over 45 take HRT, either in the form of estrogen alone or in combination with progestin.
  • A new study shows that women taking HRT, especially the combination formula, experience an increasing risk of breast cancer for each year they have been on the medication.
  • Experts warn physicians and patients to carefully weigh the risks and benefits of HRT and remind them not to overlook lifestyle changes as an option to control postmenopausal symptoms.

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