[Immunomorphological and ultrastructural characteristics of hypophyseal adenomas in prolactinemia patients].

It was shown by means of electron microscopy and immunohistochemical study that in 11 of 15 patients with high preoperative prolactinemia the tumor consisted mainly of prolactin-containing cells. Small groups of them occurred in the tumors of 2 patients, whereas in 2 other cases prolactin was not detected in the tumor cells by immunohistochemical method. Electron microscopy demonstrated hypophyseal oncocytomas in these 2 cases. Appreciable differences in the blood prolactin concentration, depending on the tumor ultrastructure, were not observed.