[Pathological study of 23 cases of nonfunctional pituitary adenoma].

23 cases of nonfunctional pituitary adenoma were studied with light and electron microscopy as well as with immunohistochemical stains PAP technique. Under routine light microscopy, 17 cases were chromophobic adenomas; anyhow, electron microscopy showed that there were 6 cases of oncocytoma; 7 cases of undifferentiated cell adenoma; 4 cases of gonadotropic adenoma; 4 cases of mixed adenomas 1 cases of sparsely granulated GH cell adenoma and 1 case of sparsely granulated PRL cell adenoma. Immunohistochemical stain showed: null cell adenomas 7 cases, FSH cell adenoma 3 cases, LH cell adenoma 1 case, GH cell adenoma 2 cases and other mixed adenoma 10 cases. Therefore, the nonfunctional pituitary adenoma is actually a mixture, and the null cell adenoma was only about 1/3 in this series. Among them, most of the hormones gave no function expression themselves.