MATURATION OF VAGINAL AND ENDOMETRIAL EPITHELIUM IN POSTMENOPAUSAL BREAST-CANCER PATIENTS RECEIVING LONG-TERM TAMOXIFEN

To assess the estrogenic effects of tamoxifen on vaginal and endometri al epithelium and to investigate whether these changes are associated with any pathological findings in the endometrium, 53 postmenopausal b reast cancer patients receiving longterm tamoxifen and 52 control brea st cancer patients without any hormonal treatment were examined. Patho logical findings in the endometrium were evaluated by hysteroscopy and curettage. The main outcome measures were the maturation index in Pap anicolaou (Pap) smears, estrogen-like epithelial changes in the endome trium, serum concentrations of gonadotropins, sex hormone-binding glob ulin (SHBG), estradiol (E2), and testosterone (T). Informative Pap sme ars showed estrogenic effects in 89% (41/46) of the tamoxifen group an d in 49% (22/45) of the control group, and in endometrial aspiration s amples in 71% (32/45) and in 41% (19/46), respectively. These changes were associated with increased concentrations of serum E2 in the contr ol group but not in the tamoxifen group. All five patients (11%) with endometrial polyps in the control group showed estrogenic endometrial changes, whereas among 14 women with polyps in the tamoxifen group, 9 showed estrogenic changes and 5 endometrial atrophy. Endometrial adeno carcinoma was found in 3 patients in the tamoxifen group and in 2 in t he control group. Pap smears showed atrophy in 2 patients in the forme r and in one in the latter group. These findings confirmed estrogen-li ke effects of tamoxifen on the vaginal and endometrial epithelium in p ostmenopausal breast cancer patients, but these were not closely assoc iated with benign or malignant endometrial lesions. (C) 1994 Academic Press, Inc.