Proliferation parameters for pituitary adenomas.

In this review, the value of assessing proliferation parameters in surgically resected pituitary tumour tissue is analyzed. Histological examination of basal dura biopsies identifies invasive growth even when intraoperatively not apparent to the surgeon. Determination of DNA-polymerase activity, Ki-67 immunohistochemistry and DNA-flow-cytometry shows a clear difference in the proliferative potential of enclosed and invasive pituitary adenomas. Among the various endocrinologically differentiated groups ACTH-secreting adenomas associated with Nelson's syndrome and thyrotropinomas were the most rapidly proliferating. At present, however, our results reveal that the prognosis of an individual patient cannot be reliably predicted on the basis of such studies.