Choriocarcinoma associated with undetectable levels of human chorionic gonadotropin.

A case of choriocarcinoma is presented which developed during close follow-up for hydatidiform mole. Serum levels of beta subunits of human chorionic gonadotropin (beta-HCG) were assessed by radioimmunoassay (RIA) before, during, and after diagnosis of choriocarcinoma and remained below the sensitivity level of the assay. To our knowledge, this is the fourth reported case where choriocarcinoma was not associated with the presence of elevated beta-HCG levels.