Endometrial mesodermal mixed tumor occurring after tamoxifen treatment:: Report on a new case and review of the literature

Background: Anti oestrogenic treatment is widely used for breast cancer treatment and prevention of recurrence. Because of concomitant estrogenic effects, tamoxifen exerts carcinogenic properties on the endometrium. Although secondary endometrial cancers usually present as pure adenocarcinomas, other types of rare tumors have also been reported. Patients and methods: Herein we describe the clinical, pathological as well as therapeutic aspects of a new case of endometrial mesodermal mixed tumor occurring after long-term tamoxifen therapy. Results: The present case occured five years after cessation of a five years tamoxifen treatment. The patient failed to respond to doxorubicin and cyclophosphamide when combined to 5-fluorouracil (5-FU), but she reached complete response when the same two drugs were used with carboplatin, suggesting the potential usefullness of platinum derivatives. Conclusions: A longer latency period might be observed for endometrial mesodermal mixed tumors as compared to adenocarcinomas and could justify a prolonged clinical and ultrasonographic follow-up of patients during and after tamoxifen treatment. When indicated, chemotherapy might require the use of platinum derivatives in this particular type of secondary tumor.