Uterine sarcoma after tamoxifen therapy for breast cancer.

Tamoxifen has been shown to significantly reduce the risk of tumour recurrence in women with receptor positive breast cancer and has been used for chemoprevention in women with both non-invasive cancer and those with a high risk of developing breast cancer. An established and accepted risk with this treatment is the increased incidence of adenocarcinoma of the endometrium. Less well recognised is uterine sarcoma, a rare and aggressive tumour accounting for under five percent of uterine malignancies, with five year survival rates in the order of 50%.