[120 biopsies of pituitary adenomas studied by immunohistochemistry and electron microscopy. A clinico-pathological...

Study of biopsies from 120 pituitary adenomas from the Hospital de Especialidades, Centro Médico Nacional, and the Hospital 20 de Noviembre, ISSSTE, were studied over a period of 55 months. 70 cases were female and 50 male. Ages varied between 18 and 67 years of age (with an average of 31 years). Histologically 41 tumors were chromophobes, 34 acidophilic, 37 mixed and 8 basophilic. 101 patients were operated by trans-sphenoidal (84.5%) and 19 were operated (15.5%) by trans-cranial approaches. 99 tumors were macroadenomas (81.1%) and 21 were microadenomas (18.9%). More than one hormone was found in the cytoplasm of 69 adenomas, although only 20 fulfilled the criteria of being plurihormonal. Those adenomas classified as "non-functional", mostly produced glycoprotein hormones corresponding to oncocytomas and null cell adenomas, from an ultrastructural point of view. 85 patients developed different degrees of visual impairment, with 30 tumoral relapses, of which 10 received radiotherapy. 40 adenomas produced prolactin, although only 29 patients developed clinical signs of hyperprolactinemia; 38 tumors contained growth hormone, of which only 25 had acromegaly; 8 tumors contained ACTH in the cytoplasm, although only 7 developed Cushing's Syndrome and 57 patients (47.5%) were classified as nonfunctional and did not show any endocrinological data. All the cases are studied with a light microscope, electron microscope, and they were all submitted to a complete set of adenohypophyseal hormone with immunoperoxidase technique.