Abstract

PIP: This editorial calls for development of quantitative assays for alpha fetoprotein (AFP) which incorporate a long-overdue uniform international standard for AFP. Statistics for presently available detection techniques are reviewed; Double-gel diffusion detects serum AFP in 1/3 white hepatoma patients and 1/3 embryonal gonadal teratoblastomas. Counterimmunoelectophoresis and electroimmunodiffusion detect AFP in more than 50% of white patients with hepatoma and a higher percentage of other racial groups. Sensitive radioimmunoassays (RIAs) can detect AFP in 85-95% of hepatoma patients; the other 5-15% are considered at present not to have AFP-producing tumors. RIAs also discern AFP in 2 other conditions; 1) gastrointestinal tract tumors and entodermally derived tumors; and 2) acute viral hepatitis. AFP in newborns is usually 1-5 mg/100 ml of blood. This level decreases (half-life, 3-5 days) during neonatancy to undetectable levels. AFP is elevated in children with 3 conditions: 1) hepatocellular carcinoma of hepatoblastoma; 2) gonadal teratoblastomas or embryonal carcinoma; and 3) ataxia telangiectasia, but not in other immune deficiency diseases. During gestation, fetal serum AFP reaches a 200-400 mg/100 ml of blood peak in the first trimester which drops to less than 5 mg/100 in newborn unbilical blood. Elevated maternal serum AFP has been shown to mark fetal distress and other pregnancy complications; these amounts are measured in nanorams and require sensitivity.