[Hormonal replacement therapy in menopause and the risk of breast cancer].

Therapeutic trials comparing hormonal replacement therapy (HRT) with a placebo are rare and bring up non conclusive results. The last meta-analysis reported included 31 non randomized studies. It did not show an increased risk of breast cancer in women treated with HRT, compared with untreated women. However, on and after the 10th year of use, the risk increased significantly, although only slightly. This increase of the risk was restricted to the current users of HRT. The three studies published after the meta-analysis showed controversial results, and did not allow any conclusion. These wide disparities between the studies have highlighted the difficulty in interpreting the results of epidemiological studies.