Breast cancer is the most common cancer in women in the Western world. Because breast cancer is estrogen-dependent, reducing estrogen secretion by oophorectomy, hypophysectomy, or adrenalectomy can cause the cancer to regress. The need for these surgical procedures was reduced by the introduction of tamoxifen, which acts as an antiestrogen by inhibiting the binding of estrogen to estrogen receptors. Tamoxifen was approved by the Food and Drug Administration in 1977 for the treatment of women with advanced breast cancer and several years later for adjuvant treatment of primary breast cancer.¹

Pharmacology and Endocrinology

Pharmacologic and Pharmacokinetic Properties

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