Papillary cystic tumor of the pancreas: an analysis of cellular differentiation by electron microscopy and immunohistochemistry

摘要: Three cases of clinically benign pancreatic papillary cystic tumors in young female patients were studied by immunohistochemistry and electron microscopy order to define the cellular nature this type neoplasm. Two showed focal cytokeratin- desmoplakin-positivity as evidence epithelial differentiation, while tumor cells all positive for vimentin--the intermediate filament protein typical (but not specific for) mesenchymal cells. Electron some cell-cell junctions, but there was no acinar or islet cell differentiation. The at least focally neuron-specific enolase, small clusters polypeptide hormone immunoreactive present (glucagon 3/3, somatostatin 2/3, insulin 2/3). However, negative synaptophysin neurofilament proteins, unlike most tumors. Trypsin chymotrypsin immunoreactivity found tumors, because many nonpancreatic carcinomas also positive, we doubt whether these two enzyme proteins can act markers that immunohistochemically presence nuclear estrogen receptors, negative. Therefore proof suggested dependence could be obtained. We conclude is a neoplasm primitive cells, may exhibit endocrine