Hormone Replacement Therapy Increases Risk of Breast Cancer

Despite the fact that Hormone Replacement Therapy was thought to have multiple benefits when given to menopausal and post-menopausal women, including reduced risk of heart disease and dementia, new studies show that it increases the risk of breast cancer.

Since 1999, multiple studies have been conducted in the U.S. and the U.K. to find the connection between the two. The correlation has been all over the proverbial map with one study in the U.K. - under the moniker "the Million Women Study" - was thought to have discovered a 50% greater chance of breast cancer in women who had used HRT. This study was found to haveshoddy results, and usually the study most referenced is a 2002 study performed by the Women's Health initiative (WHI). The study was supposed to continue for five years but was halted earlydue to the increased risk of stroke. 

A follow up study was done over a period of approximately 11 years, concluding that there is in fact a link between breast cancer and combined (estrogen and progesterone) HRT. The results recently published indicate that there is an annualized breast cancer rate of 0.60 percent for women taking HRT as opposed to a 0.42 percent risk for women who are not on HRT.

Out of 41,449 women (who had all received a negative mammogram within two years of beginning the study), 16,121 were on HRT. Out of all participants, during follow up, there were 2236 invasive breast cancers. The survival rate after diagnosis was similar for users and non-users; the users had a slightly higher mortality risk than non-users though the difference was not deemed statistically relevant, according to Policymic.  

Yet, researchers believe that HRT will continue to be used.

Though it now seems wise to use the drug for the shortest term possible to reduce potential risk of breast cancer, the drugs are still widely prescribed to treat the often intense symptoms of early menopause, as they are the only drugs that provide relief.