Teratoma of the Sellar Region: a Case Report.

The case report describes a teratoma of the sellar region with a gland forming and an immature, relatively clear undifferentiated component without signs of anaplasia. Both components express TTF-1 indicating their presumable origin in the neurohypophysis as part of the circumventricular organs. The differential diagnosis includes pituitary adenoma and spindle cell oncocytoma with inclusion of Rathke's cleft cyst, pituitary blastoma, yolk sac tumor, and other germ cell tumors. The prognosis is the same as in the immature teratomas in the gonads, specifically unclear.