Detection of an oncofetal antigen (DU-PAN-2) in sera of patients with non-malignant hepatobiliary diseases and hepatomas.

DU-PAN-2 is a high-molecular-weight glycoprotein defined by a murine monoclonal antibody (MAb) elicited against a human pancreatic adenocarcinoma cell line. This MAb recognizes an oncofetal antigen present on the surface of normal pancreatic and bile-duct epithelium, normal bronchus epithelium, and some adenocarcinomas. Elevated levels of the antigen (greater than 400 U/ml) have been detected in the serum of 79% of patients with adenocarcinoma of the pancreas and in a small percentage of patients with other adenocarcinomas, by means of a competition radioimmunoassay. Here, we have studied DU-PAN-2 antigen levels in sera of patients with a spectrum of hepatobiliary diseases and controls. Serum DU-PAN-2 antigen was elevated in 59% of 112 patients with non-malignant hepatobiliary diseases and in 50% of hepatoma patients. None of 50 healthy controls had elevated serum DU-PAN-2 levels. Patients in every category of hepatobiliary disease studied had elevated median serum DU-PAN-2 levels; the highest median levels were seen in patients with primary biliary cirrhosis (1,296 U/ml) and the lowest in stable cirrhosis (300 U/ml). Elevated serum DU-PAN-2 levels in one patient with primary biliary cirrhosis and in one patient with hepatoma returned to normal following liver transplantation. Serum DU-PAN-2 levels did not correlate well with alkaline phosphatase, 5'-nucleotidase, bilirubin, or alpha-fetoprotein. Using an immunoperoxidase technique on formalin-fixed, deparaffinized liver sections, we showed that DU-PAN-2 MAb reacted heterogeneously with bile-duct epithelium but never stained hepatocytes or hepatoma cells. While serum DU-PAN-2 levels may be useful in detecting and monitoring pancreatic adenocarcinoma, they are not specific for this disease.