Coexistent struma ovarii and serous cystadenofibroma in the same ovary.

Struma ovarii is a highly specialized and rare form of mature teratomas constituting 2% of all teratomas although small foci of thyroid tissue may be found in 5% to 15% of teratomas. Coexistence of this unusual germ cell tumor with ovarian epithelial tumors has been reported rarely; however, concomitant struma ovarii and serous cystadenofibroma has been mentioned in only 1 case report in the extensively searched medical literature. We report a rare occurrence of struma ovarii along with a serous cystadenofibroma in a 47-year-old woman.