Primary choriocarcinoma of the lung.

Choriocarcinoma was found in the lung of a 34-year-old woman. Examination of the patient's entire body, especially the genital tract, failed to disclose foci of choriocarcinoma other than that in the right lung. After surgery, the levels of human chorionic gonadotropin in the blood and the urine fell. It was concluded that the choriocarcinoma of the lung was, in fact, the primary tumor. The genesis of choriocarcinoma was also studied in ten patients who died after delivery or abortion. Autopsy disclosed trophoblasts in the pulmonary arteries in nine of these ten patients. These findings suggest that primary choriocarcinoma in women is due to pulmonary embolism caused by trophoblasts at the time of abortion or delivery.