Choriocarcinoma in mother and child, identified by immunoenzyme histochemistry.

A case of metastic choriocarcinoma after term pregnancy, with tumor localization in the kidney of a hydropic stillborn infant, is presented. The primary tumor was found in a scraping four weeks after delivery. The identity and nature of the malignant growth in mother and child were substantiated by identical immunohistochemical patterns for gonadotropin activity. Because of a positive Kleihauer test it was assumed that massive feto-maternal transfusion had caused the hydrops and intrauterine death. Now, four and a half months after starting methotrexate therapy, the mother seems to be free of tumor. Plasma human chorionic gonadotropin titers have decreased to normal.