Nonfunctioning pituitary adenoma.

A total of 14 patients (8 males and 6 females) with nonfunctional pituitary adenomas were diagnosed and underwent surgical intervention at the Kaohsiung Medical College Hospital between 1986 and 1991. Their ages ranged from 20 to 68 years with an average of 49.7 years. Eight adenomas were composed of small polygonal cells with chromophobic cytoplasm and other six were of large cells with pale eosinophilic granular cytoplasm. Immunohistochemical staining had negative staining of prolactin (PRL), growth hormone (GH), adrenal corticotropic hormone (ACTH) and thyroid stimulating hormone (TSH) in all cases, but scattered or wide spread cells containing alpha-subunit of glycoprotein hormones were found in 6 cases. Hormonal hypersecretion was absent in all of the clinical and biological pictures, as was reactivity to immunohistochemical examination. There were either very few signs of secretory activity, or none at all. CT and MRI scanning revealed 13 macroadenomas (92.9%) and one microadenoma. In seven cases, local invasion or suprasellar extension resulted in decreased visual acuity, but the most common clinical symptoms were progressive headache (78.6%), and visual disturbance (50.0%). After surgical intervention, symptoms disappeared in 74.2% of the patients.