Endocrine effects of tamoxifen in postmenopausal breast cancer patients.
The effects of tamoxifen on plasma concentration of gonadotropins, prolactin (PRL), estrone (E1), estradiol-17 beta (E2), and sex hormone-binding globulin (SHBG) were studied in 40 postmenopausal breast cancer patients. In addition, the changes induced by the drug on endometrium and vaginal epithelium were investigated. After 6-8 weeks of tamoxifen treatment, a significant decrease in FSH, LH and PRL basal levels was observed, whereas the concentrations of E1 and E2 were not significantly affected. A significant increase in SHBG levels was induced by prolonged treatment with the drug. In addition, tamoxifen caused a partial estrogenization of vaginal smears, and a weak stimulatory effect on endometrium was also apparent. These findings indicate that tamoxifen produced agonistic effects on some targets and antagonistic effects on the others.
D000368:Aged; D001943:Breast Neoplasms / Q000378:metabolism* / Q000628:therapy; D004717:Endometrium / Q000187:drug effects / Q000473:pathology; D005260:Female; D006728:Hormones / Q000097:blood*; D006801:Humans; D008408:Mastectomy; D008593:Menopause; D008875:Middle Aged; D012738:Sex Hormone-Binding Globulin / Q000097:blood; D013629:Tamoxifen / Q000494:pharmacology* / Q000627:therapeutic use; D013997:Time Factors; D014621:Vagina / Q000187:drug effects / Q000473:pathology
D006728:Hormones; D012738:Sex Hormone-Binding Globulin; D013629:Tamoxifen