A comparative study of the pancreatogram and the histological findings in 2,2'-dihydroxy-di-N-propylnitrosamine-induced pancreatic carcinoma in golden hamsters.

2,2'-dihydroxy-di-N-propylnitrosamine (DHPN) at a dose of 250 mg/kg was injected subcutaneously into 28 male Syrian golden hamsters once a week. They were sacrificed and dissected at intervals of one to two weeks beginning from the 8th week until the 20th week after the injection. Pancreatography was performed on every hamster and the chronological changes in their pancreatograms were compared with the histological findings. Marked atypical hyperplasia almost indistinguishable from carcinoma in situ was observed histologically beginning at the 13th week, and infiltrating adenocarcinoma was seen in all the hamsters in and after the 16th week. The pancreatography made it possible to depict even minute changes at an early stage that corresponded to the histological findings. One example was that a slight stenosis in the branch was detected at the 13th week and the picture of stenosis was observed in the main pancreatic duct at the 14th-15th week. This was followed by obstruction in and after the 16th week. These findings support the possibility that the neoplastic process in the hamster pancreas occurs in the branch region earlier than in the main pancreatic duct.