Study Looks at Relationship between Breast Cancer and Hormone Therapy

Hormone therapy is currently used by millions of women to relieve common symptoms of menopause.

Now, a new study looks at whether there is a link between menopausal hormone therapy and the risk of developing breast cancer.

The study looked at data on more than 100,000 women from 58 worldwide studies.

Findings suggest many types of menopausal hormone therapy show some association with an increased risk of breast cancer.

The study also showed women who received menopausal hormone therapy continued to have an elevated risk for about a decade after stopping the therapies.

Cleveland Clinic’s Holly Pederson, M.D., did not take part in the research, but advises women to not be scared by the numbers.

“While the hazard ratios can seem very scary, the absolute numbers of breast cancer events are very, very low,” she said.

Dr. Pederson said it’s important to note that the absolute risk, for an average 50-year-old woman, of getting breast cancer over the next five years, is 1.3 percent.

And when women use menopausal hormone therapy for five years, breast cancer risk only increases slightly, to about two percent.

Dr. Pederson said there are many women for whom the slight risk is worth the benefit for the relief of the menopausal symptoms, which is why it’s important for women to talk to their doctors to learn about their individual risks.

“A woman should have a thorough evaluation, not only for general health and those factors, but a very specific breast cancer risk assessment,” she said.

Dr. Pederson says the effects of hormone replacement on breast tissue and breast cancer risk are very complex and experts are still working to completely understand them.

Complete results of the study can be found in The Lancet.