Association between use of tamoxifen for premenopausal breast cancer and risk of uterine diseases

The association of tamoxifen use with the risk of uterine diseases, such as endometrial cancer, in premenopausal women with breast cancer is controversial. A nationwide, population-based, retrospective cohort study in South Korea found that premenopausal women using adjuvant tamoxifen for breast cancer had significantly increased risks of endometrial hyperplasia, polyps, carcinoma, and other uterine cancers, compared to those not using tamoxifen.