Uterine carcinoma in mice treated neonatally with tamoxifen.

摘要: The induction of preneoplastic and neoplastic lesions by the widely used antiestrogen Tamoxifen was studied in female mice. Outbred CD-1 mice were treated with (1, 2, 5, 10, 25 or 50 microg/pup/day) for first 5 days after birth. At 14-17 months, reproductive tract tissues examined pathological changes. In ovary, corpora lutea lacking while cysts quite common Tamoxifen-exposed at all doses; cystadenomas seen two Structural malformations epithelial hyperplasia oviduct 100% Malformations uterus, cervix, vagina also seen. Excessive vaginal keratinization not a feature although adenosis observed more often treatment than previously reported similar diethylstilbestrol (DES). most striking histological features, however, uterus. One hundred percent Tamoxifen-treated doses exhibited uterine hypoplasia focal areas basal cell lining endometrium. Progressive cellular atypias endometrium ranging from atypical to adenocarcinoma; highest incidence adenocarcinoma 7/14 (50%) 10 microg/pup/day dose group. No tumors corresponding control combined other abnormalities genital structure following neonatal suggests developing is exquisitely sensitive perturbation compounds hormonal activity. These studies provide basis future investigation into mechanisms Tamoxifen's carcinogenic effects experimental animals, risk benefit analysis prophylactic use healthy women who are breast cancer.