Different coexisting gynecological and endometrial pathologies in postmenopausal breast cancer patients treated with tamoxifen

Tamoxifen administration to postmenopausal women has been described as being associated with various endometrial and other gynecological pathologies. However, different coexisting gynecological pathologies in such patients have not yet been described. In the present study, we assessed the histopathological conditions diagnosed in endometrium, myometrium, and ovaries of 28 postmenopausal breast cancer patients who were treated with tamoxifen (study group) and compared the findings to those obtained from 14 similar patients without tamoxifen treatment (control group I) and from 28 age-matched healthy postmenopausal controls (control group II). All specimens were removed by total abdominal hysterectomy and bilateral salpingo-oophorectomy for various indications. The overall incidence of two or more different coexisting gynecological pathologies was significantly higher among the study group (92.9%) than in control group I or in control group II (42.9 and 50%, respectively; p = 0.0001). There was no significant statistical difference between the control groups. Overall endometrial (and endometrial-like) origin of pathological conditions was significantly more common in the study group (92.6%) than in control group I (50%; p = 0.00072) and control group II (32.1%; p = 0.0000), while there was no significant difference between the latter two groups. These findings suggest that there might be an association between postmenopausal tamoxifen exposure and the development of such different coexisting or specific single gynecological pathologies originating from the endometrium.