Using a double antibody radioimmunoassay test, a-fetoprotein was elevated (i.e., over 40 ng/ml) in 72% of patients with hepatocellular carcinoma, 75% of patients with teratocarcinoma or embryonal cell carcinoma of the testis, 23% of patients with pancreatic carcinoma, 18% of patients with gastric carcinoma, 5% of patients with colonic carcinoma, and 7% of patients with bronchogenic carcinoma studied. I n contrast to these positive findings in patients with cancer, none of the 210 normal controls over 1 year of age and only 1 of the 300 patients with chronic nonhepatic diseases other than ataxia telangiectasia had elevated levels. All of the 40 patients studied with the immunodeficiency disease, ataxia telangiectasia, had elevated AFP levels in accord with the view that these patients have a defect in organ differentiation. T h e radioimmunoassay for AFP.was of special value in monitoring the effectiveness of therapy of certain forms of malignancy (e.g., hepatocellular carcinoma, embryonal cell carcinoma, and teratocarcinoma of the testis), since the product of a few tumor cells was detectable with this assay when AFP was undetectable as assessed by agar diffusion tests and when the residual tumor could not be detected by other clinical parameters.
Cancer 34:1510-1515. 1974.
VER THE PAST 10 YEARS THERE HAS BEEN an intense interest and excitement in studies of a special group of proteins associated with neoplasms-the oncofetal proteins:3."10 These proteins are present in the biological fluids of tlie fetus and of patients with certain forms of cancer, but are absent or in exceedingly low concentration in { h e serum of normal adults. T h e demonstration of such proteins provides valuable leads for basic cancer research concerned with the nature of malignant transformation. In addition, the quantitation of these oncofetal proteins in the serum is of great value in the diagnosif and in monitoring the treatment of some forms of cancer. This is especially true when quantitative radioimmunoassay tests of great sensitivity are utilized.
T h e first of the oncofetal proteins to be