Immunohistochemical studies of mucin antigens in pancreas and intrahepatic bile-duct tumors

Abstract

Our previous studies of pancreatic and intrahepatic bile-duct tumors revealed that MUC2 mucin (“secretory mucin”, detected by a polyclonal antibody, anti-MRP) was highly expressed in intraductal papillary-mucinous tumors of the pancreas (IPMTs) and bile duct cystadenocarcinomas of the liver (BDCs) with expansive growth pattern and favorable prognosis, whereas it was rarely or not expressed in invasive ductal carcinomas of the pancreas (IDCs) and cholangiocarcinomas of the liver (CCs) with invasive growth pattern and poor prognosis. In contrast, MUC1 mucin (“membrane-bound mucin” detected by the monoclonal antibody, DF3) was rarely or not expressed in IPMTs and BDCs, but was always expressed in IDCs and CCs (Cancer 71:2191–2199, 1993;Int J Cancer 55:82–91, 1993). The results of these studies suggest that the difference in the expression of MUC1 and MUC2 mucins is a useful indicator of malignant potential in neoplasms of the pancreas and intrahepatic bile duct. This article is a review of our previous studies described above. In addition, we present longer-term follow-up data for the cases reported in our previous studies as well as demonstrating pathological prognostic factors, such as lymph node status, lymphatic infiltration, and perineural invasion. We also examined several additional cases of IPMTs and analyzed the same prognostic factors. We could confirmed the findings of our previous studies, and found that most IPMTs and BDCs with a MUC1(−) and MUC2(+) expression pattern showed less aggressive pathological factors than most IDCs and CCS with a MUC1(+) and MUC2(−) expression pattern.