Malignant Struma Ovarii Detected Incidentally Due to Contralateral Ovarian Torsion

Abstract

Struma ovarii is a rare and highly specialized form of ovarian teratoma, in which thyroid tissue is the exclusive element (>50%). It comprises about 2% of all teratomas, and the majority of struma ovarii is benign tumor. But malignant struma ovarii, which showed malignant cell change arising in the benign struma ovarii, rarely reported. Here, we report an incidentally detected case of papillary thyroid carcinoma arising in the struma ovarii due to contralateral ovarian torsion in a 80-year old female.