Persistent gestational trophoblastic neoplasia after partial hydatidiform mole - Incidence and outcome

OBJECTIVE: To report the Sheffield experience with persistent gestational trophoblastic neoplasia (GTN) after partial hydatidiform mole (PHM) and to review worldwide experience. METHODS: All PHMs registered at the Sheffield Trophoblast Centre between 1991 and 2004 were included in this retrospective study. Any case of PHM leading to persistent GTN was reviewed centrally by an expert gynecologic pathologist. Clinical features, treatment and outcome were recorded. RESULTS: During the 14-year study period 3189 PHMs were registered. Forty-one developed persistent GTN. Central histopathology review confirmed PHM in only 14 cases (0.91% of all those registered). Twelve scored low and 2 high risk according to International Federation of Gynecology and Obstetrics 2000 criteria. During the same period, 271 cases of persistent GTN originally registered as complete hydatidiform mole were reviewed; 3 were found to be PHMs (2 low, 1 high risk). In all, 15 of 17 persistent PHMs required chemotherapy. CONCLUSION: Persistent GTN requiring chemotherapy can occasionally occur after PHM; surveillance of all cases continues to be recommended.