[en] Estrogens ; Estrogens and Progestins ; Tibolone ; Hormone replacement therapy ; Breast cancer
[en] Clinical and experimental studies indicate that combined unique conjugated estrogens and medroxyprogesterone acetate moderately increase the risk of breast cancer in postmenopausal women. Classically, hormone replacement therapy is contra-indicated in women with a past history of breast cancer due to the fear of recurrence. However, these postmenopausal patients complain about hot flushes and adjuvant hormonal therapies (such as aromatase inhibitors, SERMs and Tamoxifen...) aggravate their symptoms. Observational studies and their meta-analyses do not show a deleterious effect but rather a beneficial impact of hormone replacement therapy among women with a past history of breast cancer. We summarise all these studies and their biological, clinical and epidemiological interpretations. We conclude that short term hormone replacement therapy is safe among those women requesting a replacement therapy after complete information. It is however advisable to conclude definitely only when prospective randomised trials with estradiol or tibolone (a promising alternative) will be available. Such ongoing studies will allow to conclude definitely the possible benefits and risks of hormone replacement therapy among patients with a past history of breast cancer.