Secretory endometrial adenocarcinoma in a patient on tamoxifen for breast cancer: a report of a case.

Well-differentiated endometrial adenocarcinoma of the secretory type (FIGO Grade 1) with minimal myometrial invasion occurred in a postmenopausal patient on tamoxifen therapy 5 years after mastectomy for breast carcinoma. We believe that this is the first report of secretory carcinoma of the endometrium associated with tamoxifen use. This unusual pattern of low-grade endometrial carcinoma adds to the spectrum of uterine neoplasia associated with tamoxifen therapy.