Abstract SE-4-1
A Few Things About Pituitary Adenoma Pathology Donald Ming-Tak Ho Department of Pathology and Lab. Medicine, Taipei Veterans General Hospital Department of Pathology, National Yang Ming U. School of Medicine
Pituitary adenomas are benign neoplasm of adenohypophysial cells and consist of 10% of surgically removed intracranial neoplasms. The classification of pituitary adenomas has been evolved through histologic classification, ultrastructral classification, and immunohistochemical classification. In our institute, we adopt immunohistochemical classification using immunohistochemical staining of all pituitary hormones, i.e., PRL, GH, ACTH, FSH, LH, and TSH to classify pituitary adenomas since 1985. It was found that gonodotroph adenoma and plurihormonal adenoma are the most commonly encountered tumors, the former consists of around 1/3 of cases and the latter consists of slightly more than 1/4 of the pituitary adenomas in our surgical pathology file. In this presentation, the key features of these two tumors are presented based on the observations of our materials. As though the majority of pituitary adenomas are slow growing tumors, some are more aggressive and have a faster growth rate. By using MIB-LI, the most useful proliferative marker to date, the growth velocity of pituitary adenomas could be estimated. The presentation is based on our published materials and detailed information could be obtained from the references listed below. References: 1. Ho DM, Hsu CY, Ting LT, Chiang H. The clinicopathological characteristics of gonadotroph cell adenoma: A study of 118 cases. Hum Pathol 1997; 28: 905-11. 2. Ho DM, Hsu CY, Ting LT, Chiang H. Plurihormonal pituitary adenomas: immunostaining of all pituitary hormones is mandatory for correct classification. Histopathology 2001; 39:310-9. 3. Hsu CY, Guo WY, Chien CP, Ho DM*. MIB-1 labeling index correlated with magnetic resonance imaging detected tumor volume doubling time in pituitary adenoma. Eur J Endocrinol 2010; 162:1027-33. (*corresponding author)
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