Histogenetic classification of exocrine pancreatic carcinomas

The structures of normal ductal and ductular epithelium were compared with cytological peculiarities of pancreas carcinoma. This provided the basis on which to propose histogenetic classification of exocrine pancreas carcinoma. Most of the pancreas carcinomas are adenocarcinomas and originate from small lateral ductules. Preneoplastic ductal alterations, such as proliferation of ductal epithelium, adenomatous dysplasia, and light-cell transformation, may be topographically distinguished from ductular changes, including centroacinic hyperplasia, oncocytic transformation, microglandular metaplasia, ductulo-acinic metaplasia, hepatocellular metaplasia, and peri-insular metaplasia. The close correlations that exist between ductular and acinic cells may be summarised under the cover term of terminal ductulo-acinic intercalated duct complex. Dysplasia is generally accompanied by decline in neutral glycosaminoglycans and occurrence of unsubstituted sialomucin of the embryonic type.