Intrasellar schwannomas: report of two cases.

Abstract

The complex regional anatomic features surrounding the sella turcica make the differential diagnosis of intrasellar and parasellar lesions complicated. Sellar and parasellar schwannomas are rare. With the exclusion of parasellar schwannomas arising from cranial nerves within the cavernous sinus and extending into the sella, there have been only two reported cases of true intrasellar schwannomas. We describe the clinical, radiological, and pathological features of two cases in which the histopathological diagnosis of schwannoma was confirmed with immunohistochemical analyses and/or electron microscopy. The two cases were grossly resected via a transsphenoidal approach. Follow-up monitoring revealed no evidence of recurrence. Schwannomas may atypically occur in the sellar region, in which they demonstrate the typical light microscopic, immunohistochemical, and ultrastructural features observed in the peripheral nervous system. New and existing hypotheses regarding the histopathogenesis of intrasellar and parasellar schwannomas are presented.