Carcinosarcoma of the uterus: Possible sequelae of long-term tamoxifen therapy for breast cancer

Carcinosarcoma (CS) of the uterus is rare and accounts for 1–2% of all uterine malignancies, occur commonly in postmenopausal women. These are highly aggressive tumors with poor prognosis and often present at advanced stage. Tamoxifen (TAM) has been known to increase the incidence of endometrial carcinoma from 1 to 2 cases per 1000 women/year and of uterine sarcoma from 0.04 to 0.17 cases per 1000 women/year. TAM has weakly estrogenic properties that can produce endometrial cell proliferation and, consequently, TAM use increases the risk of endometrial cancer by approximately two- to three-fold. Currently, no consensus is present regarding the management of Uterine CS. However, surgery plays an important role in the management along with chemotherapy (CT) and radiotherapy as an adjuvant. We report a case of a woman who developed malignant mixed mullerian tumor of uterus after taking TAM for 6 years as adjuvant hormonal therapy for breast carcinoma.