New HRT study shows doubling of cancer risk
pharmafile | October 29, 2003 | News story | Research and Development |
A new study of over one million UK women has confirmed an increased risk of breast cancer from all forms of hormone replacement therapy.
The Million Women Study funded by Cancer Research UK, the NHS Breast Screening Programme and the Medical Research Council found current and recent use of HRT significantly increases the chance of breast cancer.
In particular, oestrogen plus progestagen combination treatments were found to double the risk of developing the disease.
Around 1.5 million women in the UK take HRT, with around half taking combination treatment, with products marketed by a number of companies including Wyeth, Novartis and Pfizer.
In comparison, Organon Livial (tibolone), which mimics the activity of hormones, was found to increase risk by 45%, while oestrogen only HRT, given to women with hysterectomies, increased the risk by 30%.
The study backs up findings from a similar large-scale US study which was halted early in 2002 when the link between combination HRT and increased risk of breast cancer and coronary heart disease and stroke became clear.
The global HRT market was already in slow decline before the study was released, but the growing body of evidence has hit all the leading players. Wyeth UK market leading Prem Range which includes Prempak-C, Premique Cycle and Premique combination products saw its earnings fall by 4% in England last year to just over 30 million.
Companies have responded by producing new low-dose HRT products, with Schering Angeliq recently approved in Europe, and low-dose versions of Wyeth US range now on the market.
Cancer Research UK estimates an extra 20,000 breast cancers were caused by HRT use in the UK, with combination treatment accounting for 75 % of these.
But Professor Valerie Beral, Director of the Cancer Research UK epidemiology unit lead author of the new study says women on combination HRT must look at their options carefully.
"Women need to weigh the increased risk of breast cancer caused by the addition of progestagen against the lowered risk of uterine cancer."
"Comparing the risks is by no means simple, and women may well want to discuss options with their doctor."
The Committee on the Safety of Medicines has reviewed the data and has written to all health professionals, stressing that short-term HRT is still of beneficial, but those on treatment for over a year should consult their doctor about the risks.
