[Malignant struma ovarii: a case report].

Malignant transformation of struma ovarii is exceptional (less than 1%). The histolological diagnosis of malignancy is difficult especially in the well differentiated forms. Immunohistochemistry is highly contributive in the anaplastic forms. The prognosis is relatively favorable except for the metastatic and undifferentiated forms. We report a case of malignant struma ovarii with metastasis observed in a 65-year-old woman who died rapidly from her disease. In light of this observation, we discuss the diagnositic, management and outcome features of these particular tumors.