Published Dec 16, 2019

Breast Cancer Risk For Post Menopausal Women — Taking Hormones Can Increase Your Risk

While estrogen alone for menopausal hormone therapy actually decreased breast cancer risk, estrogen combined with progestin increases risk, and the effects of both hormones last for a long time.

Zara Sternberg

Details

Hormones and Breast Cancer Risk in Post-Menopausal Women

After menopause, some women take hormones to help with hot flashes and vaginal discomfort, among other post-menopausal symptoms
Taking estrogen alone decreases long-term breast cancer risk, according to new findings
Researchers find that taking estrogen plus progestin increases long-term breast cancer risk

For women who take hormone replacement therapy to relieve the sometimes very uncomfortable symptoms of menopause, there is important news about the risk for breast cancer.

Older women sometimes take hormones to address symptoms of menopause including hot flashes and vaginal discomfort. Taking hormones has also been widely proven to prevent bone loss and reduce bone fractures for older women. Hormones were once routinely prescribed, until large clinical trials demonstrated the health risks, including increased risk for cancer.

New information from researchers at UCLA confirms that women who took the hormone estrogen after menopause decreased their risk for breast cancer. The study also confirms that women who took estrogen plus progestin increased their risk of breast cancer. That’s actually been fairy well documented, however the new research shows that these changes in risk follow women for more than 15 years.

“It is reassuring for women with intractable menopausal symptoms that short-term therapy with [estrogen hormones] alone decreased their risk of breast cancer,” Dr. Charles L. Shapiro, a professor at the Icahn School of Medicine at Mount Sinai, tells SurvivorNet.

Researchers looked at data from two large trials which took place at 40 centers across the U.S. from 1993 to 1998. The data involved more than 27,000 women ages 50 to 79 with no prior breast cancer, and information was collected over more than 15 years.

After initial data was collected, the study’s authors found that 238 out of 5,310 women who took estrogen alone were diagnosed with breast cancer. After 16.1 years of cumulative follow up, 520 women had been diagnosed with breast cancer.

At the same time, researchers initially found that 360 out of 8,506 the women who took both estrogen and progestin breast cancer were diagnosed with breast cancer. After 18.3 years of cumulative follow up, 1,003 of the women had been diagnosed with breast cancer.

Risk Factors for Breast Cancer

This study demonstrated that hormones, depending on the type and combination, can increase or decrease risk for breast cancer, and that the effects of those hormones can last a long time. That makes hormones therapy a “risk factor” for breast cancer. But hormones aren’t the only risk factors for breast cancer.

The risk varies within each age group, and breast cancer becomes increasingly more common as women age. At age 30, for instance, the risk is one in 227, according to the National Cancer Institute. By age 70, the risk is one in 26.

Dr. Elizabeth Comen, medical breast cancer oncologist at Memorial Sloan Kettering Cancer Center, on risk factors for breast cancer

While the key risk indicators are age and family history, there are a whole host of risk factors, many of which our medical advisor Dr. Elizabeth Comen covers in this video. The American Cancer Society breaks them down into lifestyle factors like being overweight and not having children and factors you can’t control, like inherited genes and race. Understanding your breast cancer risk factors is obviously very important.

Learn more about SurvivorNet's rigorous medical review process.

Zara Sternberg is a journalist and writer for SurvivorNet. Read More

SurvivorNetTV.
Hope. Science.
Inspiration.

WATCH NOW