[Immunohistochemical examination of carcinomas in the pancreatoduodenal region and its non-malignant counterparts using monoclonal antibodies against Lewis blood group-related antigens and sialyl Tn antigen].

Forty cases of carcinomas in the pancreatoduodenal region (carcinoma of the ampulla of Vater: 11 cases, carcinoma of the pancreas head (CPH): 12 cases, carcinoma of the inferior common bile duct (CIBD): 17 cases) and its non-malignant counterparts were examined immunohistochemically, using monoclonal antibodies against four Lewis (Le) blood group-related antigens and sialyl Tn antigen. TKH-2 (anti-sialyl Tn) reactivity, which is almost negative in non-malignant counterparts except for goblet cells in the duodenum, is highly positive in carcinomas, therefore, sialyl Tn antigen can be an excellent tumor marker in this region. Lex and sialyl Lex-i antigens have been regarded as pancreatic cancer-associated antigens, however, this study suggests that Lex and sialyl Lex-i are more useful markers for CIBD than CPH. Above findings imply that altered regulation of glycosyltransferase activity is associated in malignant state of the pancreas and inferior common bile duct.