1996g-074 adverseeffects androgenantagonists antagonists antiandrogens antineoplasticagents breast breastneoplasms cancer congresses contraceptiveagents contraceptives control drugtherapy estrogen estrogenreplacementtherapy etiology female hormone-dependent hormonetherapy neoplasms oral oralcontraceptives physiologicaleffect prevention prostate prostaticneoplasms selectiveestrogenreceptormodulators sideeffects tamoxifen therapeuticuse wp870r584e1996