Abstract
Recent methodological advances in immunohistochemistry, ultrastructural techniques, hormonal assays, resolution imaging and molecular biology techniques have provided new insights into the pathology, functions, and cytogenesis of pituitary adenomas. Pituitary adenomas have been classified historically on the basis of tinctorial affinities, followed by ultrastructure and immunohistochemistry. The current development of technologies necessitate a new classification of pituitary adenomas which integrates this enormous information as well as previous clinical information. We demonstrate here the molecular morphology of pituitary adenomas using a non-radioisotopic in situ hybridization technique. The expression of the pituitary-specific transcriptional factor (Pit-1), and nuclear receptors including estrogen receptor, thyroid hormone receptor and retinoid X receptor genes in adenomas are demonstrated. This new information provides deeper insights into understanding the pathophysiology and pathogenesis of adenomas. We propose a new clinico-cytofunctional classification of pituitary adenomas which is based on clinical manifestations and integrates the information concerning the biology, images, functions, and ultrastructure. This classification which corresponds to current advances will not only provide pertinent clinical information but will also facilitate better understanding of the biology and nature of these complex lesions.
