A COLLABORATIVE STUDY FOR THE EVALUATION OF LECTIN-REACTIVE ALPHA-FETOPROTEINS IN EARLY DETECTION OF HEPATOCELLULAR-CARCINOMA

Lectin-affinity electrophoretic separation of serum alpha-fetoprotein (AFP) was carried out using AFP Differentiation Kits, which used Lens culinaris agglutinin-A (Kit L) and erythroagglutinating phytohemagglut inin (Kit P). Separated AFP bands were detected with a sensitive antib ody-affinity blotting technique and determined quantitatively by densi tometry, and the results were expressed as percentages of the intensit y of total AFP bands. Sera from 424 patients with acute hepatitis, chr onic hepatitis, liver cirrhosis, hepatocellular carcinoma, and extrahe patic tumors were assayed for proportion of AFP present as Lens culina ris agglutinin-A-reactive AFP (AFP-L3) and erythroagglutinating phytoh emagglutinin-reactive AFPs (AFP-P4+P5). From the maximum Youden indice s determined, cutoff levels were set at 15% for both AFP-L3 and AFP-P4 +P5 to discriminate between patients with chronic hepatitis and liver cirrhosis and patients with hepatocellular carcinoma. AFP-L3 and AFP-P 4+P5 showed sensitivities of 55.3 and 61.0% at specificities of 93.9% and 82.3%, respectively. Thirty-eight % of tumors that measured less t han 20 mm in diameter were positive for AFP-L3 and AFP-P4+P5. AFP-L3 e xceeded the cutoff level of 15% 4.0+/-4.9 months before detection of h epatocellular carcinomas by imaging techniques with a sensitivity of 4 8% and a specificity of 81%. Thus, these tests are useful for the earl y detection of hepatocellular carcinomas in patients with hepatitis or liver cirrhosis.