HRT ‘doubles risk of breast cancer’

New research has found that certain kinds of Hormone Replacement Therapy (HRT) can double a woman’s risk of developing breast cancer.

More than a million women in the UK take HRT and it is thought that the drugs may be responsible for an extra 20,000 cases of the disease in Britain.

The largest study of its kind, looking at over a million women, found that the single oestrogen-only pill moderately increases the risk of breast cancer, but the combined oestrogen- progestagen pill doubles the risk.

The publication of the study in the Lancet today has prompted the Government’s medical watchdog, the Committee on Safety of Medicines, to issue urgent advice telling all GPs to discuss the findings of the study with patients.

The committee stressed that short-term HRT use can be beneficial, but those taking it for more than a year should take the risks into account and discuss them with their GP. The study also showed that if a woman stopped HRT, the risk of developing breast cancer dropped back to that of non-users within a few years.

The study found for every 1,000 women who use HRT for 10 years from the age of 50, there will be an additional 19 cases of cancer in those using the combined oestrogen and progestogen version and an extra five in those using oestrogen-only HRT.

Breast cancer affects 20 women in every 1,000.