Women using hormone replacement therapy (HRT) to deal with symptoms of the menopause should discuss with their doctor whether or not to continue using the treatment and how long the therapy is necessary, breast cancer experts have advised.
The warning follows research published in the Lancet journal which found the risk of developing breast cancer as a result of taking HRT for five or 10 years was higher than previously thought.
The study by researchers from the University of Oxford also found the risks associated with menopausal hormone therapy (MHT) can persist for more than a decade after usage stops.
The study, which used data from more than 100,000 women, found that for every 100 women using oestrogen plus daily progestagen MHT, two extra cases of breast cancer were found between ages 50 and 69. Researchers said that if the associations were causal it meant MHT had already caused around one million breast cancers in western countries – one-twentieth of the total since 1990.
The main problem is how long women stay on the therapy, according to Prof Séamus O’Reilly, consultant medical oncologist at Cork University Hospital, who warned that HRT had joined the list of preventable causes of breast cancer which included alcohol consumption and obesity.
‘Renewal conversation’
HRT needs to be administered “judiciously and for a short duration of time”, said Prof O’Reilly. “Professional bodies have always recommended to limit it to as short as possible. It is needed for some women with severe menopausal syndromes – a short course of HRT may be helpful. The problem is it’s easy to renew prescriptions. This is an example of where the renewal conversation needs to be as robust as the initiation conversation.”
He added: “The biggest thing is that women on HRT need to talk to their doctor about whether or not they should stay on it. That conversation can save lives.”
Prof John Crown, consultant medical oncologist at St Vincent’s private hospital, agreed that women should not make the decision to go on HRT lightly, warning that there was a “not-irrelevant risk associated” with taking it.
While the Lancet study presents findings that medical practitioners were generally aware of, its conclusions, which show that women who use HRT for longer periods of time are more likely to develop breast cancer, are “very authoritative” and “fairly definitive”, said Prof Crown.
Patients should be reassured that this is nothing to be concerned about and comforted to remain on their HRT
“It’s very sad that these pills have this problem because they’re so incredibly good at helping women who have disruptive symptoms from the menopause with their quality of life. Nobody should be getting HRT without a really good chat with their doctor.”
Interesting points
Dr Deirdre Lundy, GP and women’s health specialist with the Irish College of General Practitioners (ICGP) said while the review presented a few interesting points on HRT, it “does not bring any additional information to the table” and “does not change current prescribing guidelines”.
“Patients should be reassured that this is nothing to be concerned about and comforted to remain on their HRT if they find benefit from it,” said Dr Lundy, adding that the risk of being diagnosed with breast cancer because of obesity was much higher than the risks associated with HRT usage. The HRT risk was about on par with the risk among women who drink more than two units of alcohol per day, she said.
However, general practitioner Dr Susan Smith reported in a Twitter thread on Friday that being overweight had a similar absolute increase in risk to taking the oestrogen-only HRT.
Responding to the report, chief executive of Breast Cancer Ireland Aisling Hurley also urged women to check themselves regularly and always take up their mammogram appointments, in particular women who are taking HRT.
“It’s about appreciating the report’s statistics and then balancing the risks to empower themselves,” said Ms Hurley.
