Immuno-histochemical investigations with monoclonal antibodies against CEA-related components in chronic pancreatitis and pancreatic carcinoma.

This is a report on an immuno-histochemical investigation with monoclonal antibodies (MAbs) 431/31, 250/183 and 374/14 against CEA and CEA-related antigens in 60 cases of chronic pancreatitis and pancreatic carcinoma. The positive reaction of normal pancreas with MAb 374/14 depends on age. Fetal pancreas and that of infants is negative. The epithelium of the medium-sized ducts of pancreases of children show a weakly positive reaction. The pancreas of adults shows a superficially-bound intense reaction in ductal epithelium. The control pancreases of all ages did not react with MAbs 250/183 and 431/31. Chronic pancreatitis shows a more intense reaction with MAb 374/14 at the surface of the ductal epithelium as compared with MAbs 250/183 and 431/31. The two latter showed a positive reaction in only 50% of the cases of chronic pancreatitis. All forms of epithelial dysplasia showed a positive reaction with the three MAbs in different localization. In the case of ductal pancreatic carcinomas the reactions are much more intense and diffuse in distribution with all three MAbs. From this we conclude that malignant duct cells display a greater number of epitopes than do the cells in chronic pancreatitis. Since two anaplastic carcinomas did not react with the three MAbs, the original epitopes disappear with dedifferentiation.