The endocrine pancreas and its tumors.

The endocrine pancreas is a complex and important gland that is essential for fuel metabolism. Morphological investigations have an important role in the study of the normal and pathological endocrine pancreas. Endocrine tumors of the pancreas represent a group of hormone-producing neoplasms that can give rise to a variety of clinical manifestations. Their cytodifferentiation and hormonal activity can be determined using a number of sophisticated morphological techniques, including immunohistochemistry, electron microscopy, and ultrastructural immunocytology. In some cases, tissue culture has a role in the analysis of their hormonal profile. Recent advances in molecular biology have paved the way for studies of the factors that underlie cytodifferentiation and pathogenesis of these lesions. Transcription factors may determine hormonal activity and differentiation of cell types in the endocrine pancreas, and transgenic mouse models have shed light on the development of endocrine tumors in the pancreas.Endocr Pathol 4:120-130, 1993.