Pituicytoma: report of two cases and clues regarding histogenesis

The pituicytoma is a rare primary tumor of the neurohypophysis. Although histologically benign, the location and vascular nature of these tumors can make surgical resection difficult. We present a report of two patients with pituicytomas and review the literature regarding treatment and prognosis for this unusual lesion. Possible histogenetic relationships of this tumor with other pituitary neoplasms are presented.

Patient 1 was a 45-year-old man who presented with a 5-year history of decreased libido. He was found to have a 2-cm suprasellar mass on a magnetic resonance imaging scan. Patient 2 was a 48-year-old man who presented with multiple endocrine complaints. He was found to have an intrasellar mass on magnetic resonance imaging.

Patient 1 underwent a right frontal craniotomy, with a subtotal resection of the suprasellar mass through the lamina terminalis. The residual tumor was treated with fractionated stereotactic radiotherapy. The intrasellar mass in Patient 2 was resected via a transsphenoidal approach. On surveillance magnetic resonance imaging, the tumor was found to have recurred and expanded into the suprasellar space. The patient underwent a right frontal craniotomy for decompression and a subtotal resection of the tumor. The patient experienced a second recurrence 7 years after the initial procedure and was subsequently treated with fractionated stereotactic radiotherapy.

Pituicytomas are a distinct form of pituitary gland neoplasia that may recur if subtotally resected. These neurohypophysial tumors may contain a small subpopulation of previously unrecognized bcl-2-immunoreactive cells, whose role in the histogenesis of pituicytoma deserves further study.