Pituitary adenomas: immunohistochemical: study of 90 cases.

Pituitary tumors from 90 patients were investigated using immunohistochemical study and the results were correlated with clinical records. There were 32 benign prolactinomas and two malignant counterparts, 13 growth hormone positive tumors. 10 corticotropic adenomas, and 10 gonadotropic tumors. Four tumors showed positivity for both prolactin and growth hormone, one prolactin and gonadotropin. An example of mixed, luteinizing hormone, prolactin and growth hormone was observed. Additionally, there was an adenoma composed of two compartments secreting prolactin and growth hormone. One patient had a recurrent gonadotropin adenoma after surgical removal of the original prolactinoma. Fifteen tumors were negative for all hormones and most were nonfunctioning clinically. The clinicopathologic correlations were found to be good for prolactinoma, growth hormone positive tumors and for tumors producing both prolactin and growth hormones causing a combined feature of hyperprolactinemia and acromegaly.