Suprasellar ectopic pituitary adenoma: case report and review of the literature.

The occurrence of a totally suprasellar ectopic pituitary adenoma in a 71-year-old man is described. The tumor was attached to the pituitary stalk, extending upward toward the third ventricle. No intrasellar lesion was observed. Histological examination revealed a pituitary adenoma with large numbers of eosinophilic cells with moderate nuclear polymorphism and rare mitosis. Immunohistochemical staining revealed that the tumor cells were strongly positive for anti-adrenocorticotropic hormone antibody. A review of five previously reported intracranial ectopic pituitary adenomas revealed that two were silent corticotropic tumors and two occurred with Cushing's syndrome.