Choriocarcinoma of the mesosalpinx masquerading as congestive heart failure: ultrastructural observations of the tumor.

A 45-year-old woman suffered from hypertension and congestive heart failure for 5 months. She was found to have a choriocarcinoma of the left mesosalpinx. The final event was, in all probability, a massive pulmonary tumor embolus which occurred shortly after removal of the uterus and adnexae. The tumor was studied by immunohistochemical methods as well as ultrastructurally, and the findings are illustrated and described.