INCIDENCE, PATHOLOGY, AND RECURRENCE OF PITUITARY-ADENOMAS - STUDY OF647 UNSELECTED SURGICAL CASES

The incidence of various types of unselected pituitary adenomas based on correlation of pathologic and clinical data was assessed. We invest igated 647 cases of unselected pituitary adenomas, which were surgical ly removed between 1980 and 1993. All cases were examined by immunohis tochemistry and electron microscopy. The mean age of patients was 44.0 years with 40.0 years for women (55.2%) and 49.1 years for men (44.8% ). Age distribution indicated a remarkable sex difference: 52.4% of wo men and 26.8% of men were between 21 and 40 years at the time of surge ry. Based on immunohistochemistry and electron microscopy, prolactin ( PRL) cell adenomas represented 26.3% of tumors, growth hormone (GH) ce ll adenomas 12.5%, adrenocorticotrophic hormone (ACTH) cell adenomas 1 2.4%, oncocytomas 12.4%, and gonadotroph cell adenomas 9.4%. Seventy-t hree percent of the prolactinomas occurred in women and 73.8% of the o ncocytomas were found in men. The incidence of pediatrics pituitary ad enomas was 4.6%. All 647 cases were followed up; the mean follow-up pe riod was 96.6 months. In 40 patients (6.2%), the adenoma recurred. Rec urrence was common in functioning ACTH cell adenomas (8 cases: 9.5%) f ollowed by silent adenomas (7 cases: 25.9%). Recurrence was noted afte r 2-96 months (average 28.7 months) following surgery. The shortest re mission period was found in a patient with oncocytoma followed by a pa tient with prolactinoma.