DIAGNOSIS OF HEPATOCELLULAR-CARCINOMA BY CONCANAVALIN A AFFINITY ELECTROPHORESIS OF SERUM ALPHA-FETOPROTEIN

Background. Concanavalin A (Con A) affinity electrophoresis of serum L u-fetoprotein (AFP) can distinguish hepatocellular carcinoma (HCC) fro m other malignancies when the serum AFP concentration is elevated. How ever, Con A has not been able to distinguish HCC from benign chronic l iver disease such as cirrhosis or chronic hepatitis. Methods. The Con A affinity electrophoresis of serum AFP was analyzed in patients with a serum AFP concentration greater than 50 ng/mL by antibody affinity e lectrophoresis and Western blotting in an attempt to distinguish hepat ocellular carcinoma from benign chronic liver disease. Before the assa y, the serum AFP concentrations were adjusted between 100 ng/ml and 30 0 ng/ml by concentrating or diluting the samples. Results. Of 180 pati ents with HCC, 44 (24%) had a single band and 91 (51%), 35 (19%), and 10(6%) had 2, 3, and 4 bands, respectively. All 35 patients with chron ic hepatitis had a single band. All but 1 of 72 patients with cirrhosi s had a single band. Multiple AFP bands on Con A affinity electrophore sis appear to be diagnostic of HCC. This method has a sensitivity of 7 6%, a specificity of 99%, a positive predictive value of 99%, and a ne gative predictive value of 71% for detecting HCC. The number of AFP ba nds correlated with serum AFP concentration and tumor size in patients with HCC. Conclusions. This assay is useful for distinguishing HCC fr om benign chronic liver diseases.