DIFFERENT COEXISTING ENDOMETRIAL HISTOLOGICAL FEATURES IN ASYMPTOMATIC POSTMENOPAUSAL BREAST-CANCER PATIENTS TREATED WITH TAMOXIFEN

In an attempt to assess the hypothesis that different endometrial site s may respond differently to tamoxifen exposure In postmenopausal wome n, hysteroscopic selected endometrial histology was investigated in 17 5 postmenopausal breast cancer patients who received continuous treatm ent with tamoxifen, and in 27 similar patients not treated with tamoxi fen who served as controls, In the tamoxifen-treated patients 14 (8.0% ) developed endometrial polyps. Of 14 patients, 8 (57.2%) each display ed atrophic endometrium in the same histologic specimen, 5 (35.7%) eac h had coexisting simple hyperplasia, and 1 (7.1%) other had complex hy perplasia. Another 21 (12.0%) developed simple or complex hyperplasia. The endometrial hyperplasia coexisted with atrophic endometrium in al l these patients. All these lesions were selectively identified by hys teroscopic examination prior to the endometrial biopsy, In the control group 3 (11.0%) had simple hyperplasia and 2 (7.4%) had endometrial p olyps, The above results support, the hypothesis that the endometrium of postmenopausal breast cancer patients on tamoxifen treatment may po ssess different responses to tamoxifen exposure.