Ovarian mixed germ cell tumor composed of polyembryoma and immature teratoma.

We report the case of a 41-year-old woman with ovarian mixed germ cell tumor which was composed of polyembryoma and immature teratoma and who had high serum levels of alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG). By immunohistochemical methods, AFP was found in yolk sac cells of the embryoid bodies and immature hepatoid tissues, and hCG was found in giant syncytiotrophoblastic cells. She was treated with surgery followed by cisplatin-based combination chemotherapy. She is well, and her serum levels of AFP and hCG have not been elevated for more than 4 years after the treatment.