Late recurrence of gestational trophoblastic disease.

Persistent normal human chorionic gonadotrophin (hCG) levels for a period of 1 year after treatment is considered to be a reliable criterion of complete and sustained remission in patients with gestational trophoblastic disease. This is because such patients rarely require further therapy. Two patients are presented who developed recurrent disease after being in remission for 18 and 21 months. One of the patients initially had metastatic disease in the lungs; the other had tumor in the lungs and brain. Both of the patients have remained clinically free of disease after retreatment; one patient for 31 months and the other patient for more than 4 years. The management of the patients is presented with an emphasis on the requirement for long-term surveillance. Possible mechanisms to account for the reactivation of disease after a prolonged latency period are considered.