Ectopic Production of Human Chorionic Gonadotrophin by Neoplasms

Abstract

The ectopic production of human chorionic gonadotrophin (hCG) by nontrophoblastic neoplasms was investigated by a sensitive radioimmunoassay that specifically measures hCG in the presence of human luteinizing hormone. Of 828 patients with nontesticular neoplasms, 60 had detectable hCG. A high frequency of positive responses was found in patients with carcinomas of the stomach, liver, pancreas, and breast and with multiple myeloma and melanoma. The hCG secreted by tumors and hCG normally secreted by the human placenta were studied for similarity. Immunologic similarity was shown by parallel inhibition curves in the radioimmunoassay. Both native hCG and the hCG in plasma samples from patients with neoplasms had similar Sephadex G-100 elution patterns. In addition to similar immunologic and physical behavior, the hCG in plasma samples was biologically active. The frequency and types of tumors associated with hCG production are greater than has been previously appreciated.