Intrasellar paraganglioma presenting as nonfunctioning pituitary adenoma

Paragangliomas arising in the sellar region are rare. We report a case of i ntrasellar paraganglioma of a 54-year-old man who presented with gradually decreasing visual acuity. Physical examination revealed bitemporal hemianop sia with no apparent signs of endocrinologic dysfunction. Magnetic resonanc e imaging revealed a large sellar mass believed to be a nonfunctioning pitu itary adenoma. The tumor was removed transsphenoidally and submitted for hi stologic examination. The morphologic features, based on histologic, immuno cytochemical, and electron microscopic analyses, were consistent with the d iagnosis of paraganglioma. The diagnostic morphologic features and the immu nocytochemical profile of the tumor are reported.