Hormonal treatments prescribed to women during menopause would be associated with an increased risk of breast cancer, according to British researchers.
At the onset of menopause, women suffer from many uncomfortable hormonal changes. The ovaries gradually stop functioning, leading to a decrease in estrogen level and a virtual disappearance of progesterone. This can lead to hot flashes, sleep disturbances, vaginal dryness, genitourinary disorders, or weight gain. To relieve these symptoms, many patients are prescribed hormone therapy.
But, according to a study published August 29 in the medical journal The Lancet, hormone replacement therapy (HRT) is associated with an increased risk of developing breast cancer, with the exception of locally applied estrogen gels. The researchers were able to quantify the risk for each type of treatment.
58 studies on more than 100,000 women
In total, British researchers analyzed 58 epidemiological studies involving more than 100,000 women. As a result, a 50-year-old woman treated for five years with HRT containing estrogen and progesterone continuously had a 8.3% chance of developing breast cancer within twenty years of starting treatment, compared to 6.3% for a woman of the same age without drugs. The proportion would be 7.7% for those who received treatment for the same duration with estrogen and progesterone intermittently, ie not every day, and 6.8% for those treated with estrogen alone. . And the longer the treatment lasts, the more the risk increases, the researchers note.
"The use of THM for 10 years carries a risk of breast cancer approximately twice as high as that associated with a five-year treatment, but it appears that the use of HRT for less than one year year is low risk, "says Gillian Reeves of Oxford University, co-author of the study.
"Women should know about this new information"
"Physicians must take into account the message of this study but also (take into account) the symptoms of menopause, carefully considering the risks and benefits of treatment for each woman (...) This may depend on the severity of the symptoms , contraindications to HRT, BMI (body mass index, NDLR) and may take into account the preferences of the patient, "notes Joanne Kotsopoulos, Women's College Hospital of Toronto (Canada), specializing in cancer breast, in a comment on the study.
For the Medicines and Healthcare Product Regulatory Authority (MHRA), women who take or have already taken HRT should be alert and talk to their doctor at their next consultation, asking for a breast cancer screening. "Women should be aware of this new information, so that it can be considered with the other risks and benefits of using hormone replacement therapy," said Sarah Branch, Deputy Director of the Division of Vigilance and Disease. the risk management of MHRA drugs, based on the results of this study.
"Menopause can have unpleasant side effects and HRT products can be effective in helping to relieve symptoms.No medication is totally risk-free, but it is important for women to be able to make an informed decision about the risks and harms. advantages that suit them, "she continues, quoted by The Guardian.
Many other factors can play in the development of breast cancer
This study is not the first to show an association between HRT and breast cancer. In 2002, American researchers made a lot of noise by establishing this link. As a result, the doctors had less prescribed these treatments. In France, where at least a quarter of women aged 50 to 60 were treated in this way in 2000 and 2001, HRT decreased by 62% between 2002 and 2006. At the same time, the incidence of breast cancer was decreased by 6.6% among women aged 50 to 69, a phenomenon that many experts have attributed to the decline in HRT.
However, many other factors are likely to play in the arrival of breast cancer: alcohol consumption, the weight or age of the first child, genetics or the color of the skin.
Following numerous controversies on hormonal treatments, many researchers have studied the subject. A few months ago, a Canadian research published in the journal Acta Physiologica, argued that these treatments could effectively protect the heart if women took them before menopause and not after, as is always the case. Because, its arrival is also accompanied by an increased risk of cardiovascular diseases.