Case Report and Literature Review: Endometrial Carcinoma in a Postmenopausal Patient Treated with Tamoxifen for Breast Cancer

Abstract

Tamoxifen is a selective estrogen receptor modulator. It is commonly used in the treatment of patients with hormone receptor positive breast cancer.The early breast cancer trialist group ,EBCTCG meta-analysis reported that 5 years of adjuvant Tamoxifen treatment resulted in reduction in recurrence and mortality by 47% and 26% respectively, and reduced the incidence of contralateral breast cancer by 47% (1). Tamoxifen is also used for chemoprevention in women at high risk for developing breast cancer,and those with 5-year breast cancer risk > 1.7%.  The benefit was found to be 49% in women > 35 years old(2). A number of studies have confirmed the relation between Tamoxifen and development of endometrial cancer that has a very low, yet a serious incidence. The cumulative risk of endometrial cancer with Tamoxifen use is 1.6% at five years and 3.1% if used for 5-10 yrs(3).Tamoxifen has  antagonistic and  agonistic effects. When it exerts its agonistic effect on the endometrium in postmenopausal women it may lead to a number of effects ranging from hyperplasia to endometrial cancer(3).