Three different types of alpha-fetoprotein in the diagnosis of malignant solid tumors: use of a sensitive lectin-affinity immunoelectrophoresis.

A sensitive new technique for lectin-affinity immunoelectrophoresis was applied to samples from 28 infants and children in order to distinguish the origin of elevated alpha-fetoprotein (AFP) in sera. This new immunoelectrophoresis was successfully performed within 24 hours in sera with AFP as small as 910 ng/mL. With combined use of concanavalin A (Con A) and lentil agglutinin (LCH) binding tests, AFPs were classified into three subtypes: benign hepatic condition type (six patients), hepatocellular carcinoma type (nine patients) and yolk sac type (12 patients). AFP was of hepatocellular carcinoma type in all seven patients with hepatoblastoma, and of benign hepatic condition type in six of seven patients with elevated AFP due to conditions such as hepatitis, biliary atresia, and normal newborn. The question as to whether AFP produced in "hepatoblastoma" is of benign hepatic condition type or hepatocellular carcinoma type was first answered by the information in this present report. The differentiation between yolk sac and general hepatic AFPs was completed with the Con A binding test.