According to experts the effect of HRT or hormone replacement therapy related to women getting breast cancer has been underestimated.
It has been suggested by a new study, published in the British Journal of Cancer, that women are three times more likely to suffer from breast cancer if they received treatment that combined progestin and estrogen compared to women who didn’t.
Uncomfortable symptoms of menopause, such as mood changes, depression, and hot flashes in women who are in their 50s are treated through the use of HRT. Hormone replacement therapy or HRT has two main types: In one only estrogen is used. In the other type estrogen that the body has stopped producing is replaced and progestin is added to decrease the risk of uterine cancer. This type of HRT is called combined HRT. Women can take it as a pill, a gel, a cream, an implant, or skin patches.
The new study is part of the Breast Cancer Now Generations Study led by researchers at The Institute of Cancer Research, London. The study follows more than a 100,000 women for 40 years in order to investigate how breast cancer is caused.
A total of 39,183 women were identified by the researchers. All of the women were those whose age during the start of their menopause was known. These selected women were monitored by researchers for 6 years. The monitoring was done through questionnaires that gathered data on the women’s use of HRT and the duration of their treatment.
The study revealed that a total of 775 of the women being monitored got breast cancer. According to the results of the study women were 2.74 times more likely to suffer from breast cancer if they had used combined HRT for 5.4 years on average compared to women who had never used such HRT. The researchers also found out that the risk of cancer increased with the length of use of HRT. Compared to nonusers women were 3.3 times more likely to get breast cancer if they used combined HRT for more than 15 years.
However, women who used HRT (estrogen-only) showed no increased risk of suffering from breast cancer compared to women who never used HRT. The results also shared important data showing that the risk of breast cancer came down to normal levels after a year or two once women stopped using HRT.
According to the researchers of the study the growth and development of some breast cancers being affected by the increased exposure to hormones might explain the observed higher risk of breast cancer with regards to combined HRT. The researchers went on to say that the link between HRT and breast cancer may have been underestimated by previous studies.
Anthony Swerdlow, the leader of the current study and a professor of epidemiology at The Institute of Cancer Research in London, said in a statement that, “Our research shows that some previous studies are likely to have underestimated the risk of breast cancer with combined estrogen-progestin HRT. We found that current use of combined HRT increases the risk of breast cancer by up to three fold, depending on how long HRT has been used. Our findings provide further information to allow women to make informed decisions about the potential risks and benefits of HRT use.”
Baroness Delyth Morgan, the chief executive of the breast cancer research charity Breast Cancer Now, advised that the risks and benefits related to the use of HRT need to be understood by women, and that they should discuss it with their doctors. “We hope these findings will help anyone considering the treatment to make an even more informed decision. On balance, some women will feel HRT to be a necessity. But in order to minimize the risk of breast cancer during treatment, it is recommended that the lowest effective dose is used for the shortest possible time.”