Immunoreactive human chorionic gonadotropin and its free ,B subunit in serum and ascites of patients with malignant tumors

Human chorionic gonadotropin (hCG) is a clinically relevant marker of trophoblastic and nontrophoblastic malignancies. In the present stud ies, in addition to determining serum hCG, we investigated the presence and properties of hCG immunoreactivity in ascites of patients with nontrophoblastic malignant tumors and, for comparison, in ascites caused by cirrhotic liver disease. Total hCG immunoreactivity |hCG (+hCG-/3)| was found to be elevated above the reference value (>S ID/liter) in the serum of 2 of 20 patients with cirrhosis and 11 of 20 patients with malignant tumors. For comparison, in ascites, hCG (+hCG-0) concentra tions were frequently higher than in the corresponding serum samples and exceeded 10 II /liter in 0 of 20 cirrhotic samples and in 16 of 20 malignant samples. In order to elucidate the nature of the hCG immunoreactive material, all samples were then assessed by immunoradiometric assays specific fo