[Radioimmunologic serum determinations of alpha-fetoprotein in patients with tumors of the testis (author's transl)].

Alpha-fetoprotein (AEP) serum levels were determined by a new radioimmunoassay (sensitivity about 5 ng/ml) in 47 patients with teratocarcinoma of the testis and in 58 cases with seminoma before operation and during the postoperative course of the disease. In 140 healthy adult persons normal AFP levels below 15 ng/ml were measured. Of 14 preoperative cases with teratocarcinoma, 12 (86%) showed pathologic AFP levels over 20 ng/ml up to 3875 ng/ml. Postoperatively, cases free of metastases developed normal AFP concentrations within 4 to 10 weeks, whereas cases with distant metastases retained constant or increasing pathologic levels following a clinical deterioration. Only in three postoperative cases were Ouchterlony-positive results (AFP sensitivity about 10 000 ng/ml) observed. In contrast, patients with seminoma showed normal AFP levels below 20 ng/ml pre- and postoperatively. According to the results, AFP radioimmunoassay is recommended as an important tool for the differentiation of teratocarcinoma from other tumors of the testis and as a useful parameter for the control of therapy and the course of the disease.