Uterine Sarcoma Associated with Tamoxifen Use

Abstract

Between 1978, when tamoxifen was first marketed in the United States, and April 2001, there were 43 cases, reported either to the Food and Drug Administration (FDA) or in the medical literature,¹ of uterine sarcoma that developed in women in the United States who had been receiving tamoxifen (Nolvadex, AstraZeneca) for breast cancer; these included one woman with ductal carcinoma in situ and one with stage I breast cancer. In addition, uterine sarcoma was reported to have developed in 116 women in other countries after they had taken tamoxifen for breast cancer. Primary histologic findings were consistent with a diagnosis of malignant mixed mullerian tumor. The affected women in the United States had a median age of 63 years; those in other countries had a median age of 65 years. The median duration of exposure to tamoxifen was five years in both groups. Documentation of risk factors, stage at presentation, and follow-up was incomplete, but 27 of 86 women whose cancer had been classified according to the staging system of the International Federation of Gynecology and Obstetrics (31 percent) presented with stage III or IV disease, and 38 of the 159 in the two groups combined (24 percent) were reported to have died of progressive endometrial disease.