Pituicytoma with Significant Tumor Vascularity Mimicking Pituitary Macroadenoma

A 19-year-old man presented with bitemporal hemianopsia and was found to have a large sellar and suprasellar tumor, resembling a pituitary macroadenoma. Emergency transsphenoidal approach was attempted because of rapid visual deterioration with headache. However, the approach was complicated and stopped by uncontrolled hemorrhage from the tumor. After conventional cerebral angiography and recognition of an unusual pathology, transcranial approach was achieved to prevent permanent visual loss. The final pathological diagnosis was pituicytoma with epithelioid features. Pituicytoma is a rare low-grade tumor (WHO Grade I) of pituicytes involving the sellar and suprasellar region, and originating from special glial cells of the neurohypophysis. Because of the high vascularity, the firm consistency, and invasion to surrounding neurovascular structures, a pituicytoma should be included in the differential diagnosis of a mass in the sellar and suprasellar area if the tumor shows high enhancement with vascular components. We report a case of rare pituicytoma mimicking a pituitary macroadenoma with massive hemorrhage to disturb surgery.