Massive intracranial immature teratoma with extracranial extension into oral cavity, nose, and neck.

We present a case of congenital massive intracranial teratoma with extracranial extension into oral cavity, nose, and neck diagnosed by antenatal ultrasonography at 25 weeks of gestation. The fetus was delivered by cesarean section because of massive fetal head size and severe maternal pregnancy-induced hypertension. At necropsy the tumor was found to be an immature teratoma, with no recognizable normal brain tissue. An additional finding was hepatomegaly secondary to extensive extramedullary hematopoiesis. Karyotyping of both the fetus and the teratoma revealed a normal female chromosomal composition: 46,XX.