Clinical evaluation of a monoclonal antibody to serum KM01 for the diagnosis of hepatocellular carcinoma

Abstract

In order to evaluate a monoclonal antibody KM01 which was developed in mice immunized against a human colon carcinoma cell line, serum levels of KM01 and other tumor markers were studied in patients with both hepatocellular carcinoma and liver cirrhosis and in patients with liver cirrhosis alone. The KM01 levels in the sera of 50 patients with hepatocellular carcinoma plus liver cirrhosis and 50 patients with liver cirrhosis were measured using an enzyme immunoassay method and compared with various tumor markers including α-fetoprotein (AFP), DUPAN-2,and protein induced vitamin K absence or antagonist-II (PIVKA-II). The mean serum level (±MSD.) and sensitivity of KM01 in patients with hepatocellular carcinoma plus liver cirrhosis were 734 (± 716) units/ml and 64%, respectively, they were significantly higher than those of liver cirrhosis patients ( P < 0.001). Three out of 9 cases showing negative serum AFP levels had positive serum KM01 levels. Although the sensitivity of serum KM01 level for hepatocellular carcinoma was inferior to serum AFP and plasma PIVKA-II values, the sensitivity of a combination assay of serum KM01 or AFP was increased to 88%. Clinical data of the patients with markedly elevated serum KM01 levels (more than 1000 units/ml) were compared with patients with moderately elevated levels (530–1000 units/ml); serum bilirubin and alkaline-phosphatase were statistically higher in the former group ( P < 0.01). These data suggest that the serum KM01 assay is a useful tumor marker for patients with hepatocellular carcinoma, especially in AFP negative hepatocellular carcinoma patients, and that biliary tract involvement may contribute to increased serum KM01 value.