Does tamoxifen use affect prognosis in breast cancer patients who develop endometrial cancer?
OBJECTIVE: The use of tamoxifen to prevent breast cancer and decrease recurrence is not controversial. However, the effect that tamoxifen may have in women with a history of breast cancer in whom endometrial cancer develops is unclear. The purpose of this study was to estimate whether a history of tamoxifen use is a prognostic factor for such patients. METHODS: Between 1990 and 2002, patients seen at The University of Texas M. D. Anderson Cancer Center with a history of breast cancer who developed endometrial cancer were identified. Medical records were reviewed to identify clinical, pathologic, and outcome information. RESULTS: Eighty-nine patients with a history of breast cancer in whom endometrial carcinoma developed were identified. Fifty-two percent (46/89) had a history of tamoxifen use (median duration 48 months; range 2-120 months). There were no significant differences in the clinical or pathologic features between tamoxifen users and nonusers. A history of tamoxifen use was a