Giant immature intracranial teratoma with antenatal cranial perforation.

Fetal brain tumors are very rare, and fetal survival is generally poor. Here we present a congenital intracranial immature teratoma, which was prenatally diagnosed. Prenatal ultrasonography and fetal magnetic resonance imaging detected the presence of a massive, heterogeneous intracranial tumor at 26 weeks gestational age. An intracranial tumor lacking normal intracranial structures was detected. The biparietal diameter was 13.1 cm, which is abnormally long. Fetal death occurred at 27 weeks of gestation due to cranial perforation. Postmortem histologic examination revealed the presence of an immature teratoma. Ultrasonography and magnetic resonance imaging are helpful in the prenatal diagnosis and evaluation of intracranial tumors. In conclusion, some cases of giant immature congenital teratoma develop antenatal cranial perforation.