The effects of tamoxifen therapy on the endometrium

From January 1992 to December 1998, 219 women (aged between 30 and 81 yrs; average 55 years) affected by breast cancer were treated. These women in addition to the usual adjuvant therapy, were treated with TAM 20 mg/day, for a period between 24 and 72 months (average 40). In this group there were 84 postmenopausal and 31 premenopausal women. In 8 fertile patients ovarian activity was suppressed with GnRh analogue therapy and one patient underwent attinic castration. Before performing TAM therapy, a hysteroscopic exam was done and patients were followed-up with an annual check-up. None had any endometrial side-effects after the first check-up. After two years, 31 women (26.9%) complained of endometrial alterations (hyperplasia, polyps and endometrial cancer). One women only after 6 years of follow-up, had metrorrhagia; an endometrial adenocarcinoma was found. We would like to point out the necessity of monitoring these patients with an annual check-up (transvaginal sonography and/or hysteroscopy).