Diagnosis of pituitary adenomas on touch preparations assisted by immunocytochemistry.

Touch preparations from surgically removed pituitary adenomas were studied by both routine staining and immunocytochemistry for all anterior pituitary hormones. The results were correlated with the histologic, histochemical, immunohistochemical and ultrastructural findings. Several features were recognized, some of them applicable in diagnosing various adenoma types: high cellularity, cell monomorphism, nuclear irregularities and heterogeneity of immunoreactivity, all major diagnostic criteria of pituitary adenoma.