Tamoxifen Citrate Tablets are estrogen antagonists, which play the role of estrogen resistance and are mainly used for adjuvant treatment of breast cancer or post-operative breast cancer, that is, endocrine therapy. If the immunohistochemistry after breast cancer surgery shows that the estrogen receptor is positive, it is more effective for timely postoperative treatment of breast cancer, and the success rate can reach 30%-50%, but it also has certain side effects. Because this drug has estrogen antagonistic effect, it will also be used in severe cystic hyperplasia of the breast, and the effect of medication is not good when taken orally, the treatment of severe cystic hyperplasia of the breast can be effective.