The effects of tamoxifen on the vaginal epithelium in postmenopausal women.

Although increased vaginal discharge occurs with treatment, clinicians often presume the effects of tamoxifen on the vaginal epithelium are antiestrogenic. We studied 16 postmenopausal women before they began tamoxifen treatment, at 6 months, and then at annual intervals for up to 6 years. Vaginal scrapings for cytology smears and maturation values (MV) for these were performed. MV scores increased by a mean of 32% and these were predictably related to baseline values, with greater increases seen when there were lower scores before treatment. Only one woman with an MV of 0 before treatment had no significant changes with 3 years' treatment. The effects of tamoxifen on the vaginal epithelium are influenced by the baseline hormonal milieu and are maturational in the majority of postmenopausal women.