Ductal Metaplasia of Human Exocrine Pancreas and Its Association with Carcinoma1

Monoclonal antibodies to Å“il surface markers of human exo crine pancreas were used to establish the cytotypic expression of cells forming "tubular complexes" in pancreases from six adults without carcinoma and in the nontumorous pancreatic parenchyma of 16 pancreases with carcinoma. These cells man ifested duct cell determinants. In general, the presence of cells with duct cell surface markers within the acini corresponded to the normal distribution of centroacinar cells in the 30 control human pancreases (from cadaveric donors); however, foci of abnormal acini were seen in these pancreases independent of or intermingled with the "tubular complexes." The acini in these abnormal areas were formed by a core of cells and cell processes that expressed duct cell determinants. They were partially sur rounded by acinar cells and showed slight or no lumenal dilation. While the causative agent(s), the cell(s) of origin, and the regres sion and/or progression of these lesions are yet to be deter mined, the replacement of acini by the spectrum of lesions composed of cells with duct cell surface marker is suggested to constitute ductal metaplasia.