[Hormonal replacement therapy and breast cancer]

Hormonal replacement therapy is prescribed more and more frequently to increase quality of life and decrease the symptomatic and organic consequences of the menopausal status. The different studies which analyzed the risk of breast cancer for women under hormonal replacement therapy show opposed conclusion. We reviewed articles published between 1980 and 1997 to try to conclude about the consequences of the action of this treatment in the risk of breast cancer from the characteristic of the hormonal replacement therapy and from known risk of breast cancer. Hormonal replacement therapy increases the incidence of breast cancer. Risk increase with the treatment duration and a low estrogen dose would be sufficient to palliate to the hormonal lack (< 0.625 mg/j). The risk of breast cancer becomes the same that this of women without hormonal replacement treatment when treatment interrupted. The association of estrogen and progestin should not be protective of breast cancer. But the hormonal treatment seems to be synergistic for the risk of breast cancer with late menopause, late age at the birth of first child. Hormonal treatment could increase the estrogenic period and should increased the risk of breast cancer in women with late age at menarche, late age at menopause and late age at first child. It should not increase the risk of breast cancer in women with benign breast disease, with family history of breast cancer and in nulliparous women. For women who undergone a bilateral oophorectomy before hormonal replacement treatment the risk would be the same than for women with natural menopause and without hormonal replacement treatment. However breast cancer should be diagnosed earlier in women with hormonal treatment because mammographies were made more frequently. Overall survival should not different between the women who were under hormonal therapy and theses were not.