1. Surgical castration or medical castration
Estrogen produced by the body parts related to the situation with menstruation. Pre-menopausal women, estrogen produced mainly by the ovaries, ovarian atrophy in postmenopausal women, estrogen is mainly peripheral tissue through the secretion of adrenal androgen precursors by aromatase changes made.
For premenopausal women with estrogen receptor-positive patients, ovariectomy inhibited tumor growth, and improve survival rate. But the current drug of choice in an increasing number of patients with ovarian castration. Commonly used drugs for the goserelin.
2. Tamoxifen TAM
Tamoxifen TAM is the most commonly used clinical endocrine therapy, the general usage for each 10mg, 2 times a day. The main role of the mechanism of competitive binding with the estrogen-estrogen receptor within the cytoplasm, the formation of TAM-receptor protein complex, the complex into the nucleus, inhibits cancer cell DNA and mRNA synthesis, thus inhibiting breast cancer cell proliferation. Currently considered oral tamoxifen 5 years, the best results.
3. Aromatase inhibitor
Pre-menopausal women, estrogen mainly produced by the ovary aromatase, the enzyme can make male hormones into estrogen, this process is affected by the pituitary follicle-stimulating hormone and luteinizing hormone control. In the normal feedback loop under the control of gonadotropin secretion by pituitary hormone secretion, the promotion of estrogen to counter the reduction in estrogen. Therefore, premenopausal women, aromatase inhibitors used alone was not a viable treatment option.
Post-menopausal women, the ovaries no longer produce estrogen, estrogen mainly from fat, muscle and liver tissues being loaded. This process is not the pituitary regulation of androgen by aromatase into the surrounding estrogen. In the absence of feedback regulation, so in postmenopausal women taking aromatase inhibitors work well.
Now commonly used aromatase inhibitors, letrozole, anastrozole, exemestane. Large-scale clinical trials confirm that anastrozole is better than tamoxifen and endometrial cancer and thrombotic disease incidence was significantly lower than tamoxifen. U.S. breast cancer treatment guidelines that anastrozole instead of tamoxifen can be used directly for postmenopausal hormone receptor-positive breast cancer adjuvant therapy, from and Letrozole Exemestane Tamoxifen can be used in the application process in the the different stages.
