Triamcinolone (Tamoxifen Tamxifen, TAM) is an estrogen receptor competitive antagonist for breast cancer and is the most commonly used endocrine therapy drug in recent years. It is generally believed that TAM inhibits the proliferation of breast cancer cells by competing with estrogen to bind to estrogen receptors in tumor cells. TAM binds to estrogen receptors four times faster than estrogen, while TAM dissociates from estrogen receptors 100 times slower than estrogen. TAM also binds more specifically to the antiestrogen binding site of estrogen receptors, but its effects are not yet known. The usual dose of triamcinolone acetonide is 10 mg twice daily or 20 mg once daily for 6 weeks. Increasing the dose has not been shown to increase the efficacy. As confirmed by the International Collaborative Group for the Treatment of Early Breast Cancer study, breast cancer patients benefited greatly from taking TAM for 5 years after surgery compared to 2-3 years, and therefore 5 years is recommended for routine use.