[Pituitary tumors].

Pituitary adenomas have been reported to be the most common benign intracranial neoplasms. Recent radiological advancement has resulted in incidental diagnosis of pituitary tumors such as pituitary adenomas and Rathke's cleft cysts. The most common location of pituitary adenomas is intrasellar region with or without suprasellar extension. Pituitary tumors in unusual site, however, have been reported previously, including the sphenoid sinus, suprasellar region, clivus, nasal cavity, or something like that. The sources of ectopic pituitary tumors have been thought to be migration of pituitary cells in pituitary adenomas and of squamous epithelial cell remnants of the obliterated craniopharyngeal canal in craniopharyngiomas. We describe ectopic pituitary tumors and recent knowledge of etiology and pathology of pituitary tumors. Furthermore, we mention recent advancement of endonasal transsphenoidal surgery to treat pituitary tumors.