[Tamoxifen: modern drug therapy of estrogen-dependent breast tumors].

Tamoxifen is an antiestrogen drug which is used for adjuvant therapy of patients with estrogen positive receptors in breast cancer. It is a competitive antagonist of estrogen receptors for endogenous and exogenous estradiol, but its anticancer effects cannot be explained only by its action on estrogen receptors. Its main effects are anticancer and endocrine, but it also effects on antithrombin III, HDL cholesterol and biosynthesis of prostaglandins. Low incidence of side effects is its main advantage, but not having causal effects its disadvantage.