Menopause Hormone Treatments Could Increase Breast Cancer Risk
April 2, 2012

Menopause Hormone Treatments Could Increase Breast Cancer Risk

A new study funded by the National Cancer Institute has reportedly found that long-term hormone therapy to ease the symptoms of menopause, regardless of which type of hormone is used, could increase a woman's risk of contracting breast cancer.

According to an April 1 Associated Press (AP) article, experts have long warned women that the most common form of this type of treatment -- taking pills which combine estrogen and progestin -- could increase breast cancer risk. However, the new study has found that the use of estrogen alone, a treatment used by patients who no longer have a uterus, is not as safe as previously believed if used for an extended period of time.

The researchers analyzed data collected from 1980 through 2008 as part of the Nurse's Health study, HealthDay Reporter Denise Mann said, and discovered that the breast cancer risk was 88% higher for women who had taken the estrogen plus progesterone therapy for 10 to 14.9 years versus though who did not.

"This risk more than doubled for women who used estrogen-plus-progesterone therapy for 15 to 19.9 years," Mann reported. "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 15 years. There was no increased risk seen among women who took estrogen for fewer than 10 years."

The AP reports that doctors advise women to use the lowest possible dose of any type of hormone therapy for the shortest amount of time possible, even though the actual risk of developing breast cancer by treating menopause symptoms in this way remains comparatively small.

"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," 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 Boston's Dana-Farber Cancer Institute, told Mann.

"For estrogen alone, there is more safety data for someone who wants to take it for five or six years," she added, recommending that women consider the symptoms they wish to treat and opt for vaginal hormone preparation when vaginal dryness is the primary issue, as they do not include "the systemic effects" that pills do.