[Post-menopausal endometriosis developed during tamoxifen treatment]

The authors report a case of endometriosis (adenomyosis + endometrioma) which occurred in a female patient aged 69 years, who had undergone the menopause 15 years previously and who had been taking Tamoxifen for 7 years as an adjuvant treatment for cancer of the breast. Tamoxifen, a non-steroidal anti-estrogen derived from diethylstilbestrol, has a variable antagonist/agonist so that estrogenic stimulation of the female genital tract may occur, particularly of the endometrial mucosa. The reactivation of the endometriosic foci which had become quiescent under the impact of the natural menopause, which, by iatrogenic analogy is included in the series of paradoxical uterine effects of tamoxifen.