Persistence of partial mole.

Between January 1979 and August 1984, 8 of 81 patients with partial molar pregnancy who were followed at the New England Trophoblastic Disease Center had persistent trophoblastic tumor develop. No significant clinical differences were noted between such patients and others whose partial moles did not persist. On microscopic examination, none of the initial molar specimens manifested an unusual degree of trophoblastic proliferation or atypia. In six patients, curettage immediately preceding the initiation of treatment for persistent disease revealed viable molar tissue. In four, this was associated with trophoblastic hyperplasia and atypia. All patients who had persistent gestational trophoblastic tumor achieved remission with single-agent chemotherapy. Monitoring of serum human chorionic gonadotropin levels after partial molar pregnancy is recommended to detect persistent disease and effect prompt therapy.