A new placental protein test for the presence and identification of trophoblastic tumors.

Trophoblast-specific beta1-glycoprotein (TSG) is detected in serum of patients with trophoblastic and nontrophoblastic tumors by means of immunodiffusion in agar (IDF), immunoradioautography in agar (IRA), and double-antibody radioimmunoassay (RIA), The identification of TSG is carried out by monospecific rabbit antisera. By IRA, TSG was found in serum of patients with trophoblastic tumors both before treatment (82.4%) and after surgery and/or chemotherapy (37.2%). All so-called falsepositives were associated with teratocarcinoma of the testicle. By means of RIA, TSG was also discovered in serum of patients with a variety of malignancies. In total, the TSG level was elevated in 15% of 114 cases of nontrophoblastic malignancies; as a rule, from 3 to 12 ng/ml. TSG was not detected in normal adult blood sera and in different pathological conditions.