[Breast cancer and the use of the hormones around the menopause]

Abstract

Following the publication of the 'Million women study', commotion has broken out in the media about the relationship between hormone use around the menopause and breast cancer. In this study, women were asked about possible risk factors for breast cancer, including hormone replacement therapy, prior to breast cancer screening. After an average follow-up period of 2.6 years, it was found that breast cancer more frequently occurred among women who had recently used an oestrogen-progestagen preparation (relative risk (RR): 2.00; 95%-CI: 1.88-2.12), an oestrogen preparation (RR: 1.30; 1.21-1.40) or tibolone (RR: 1.45; 1.25-1.68) than among women who had not used either of these. Methodologically, the study contains both strengths and weaknesses. However, the findings agree with those from an earlier randomised study. Current users of hormone use were more likely than never users to die from breast cancer (RR: 1.22; 1.00-1.48). For the prescription of hormone replacement therapy, the twice as high relative risk of breast cancer together with the other potentially life-threatening side effects of hormone replacement therapy need to be weighed up against the complaints which form the indication for the prescription. Therefore, the advice for hormone replacement therapy continues to be that it should, if necessary, be made available as a treatment option for a short period (3 months) and only in the case of serious and debilitating complaints. Long-term preventative use, as happens in practice, is not indicated due to the risk of relatively serious side effects.