Etoposide and cisplatin / etoposide, methotrexate, and actinomycin D (EMA) chemotherapy for patients with high-risk gestational trophoblastic tumors refractory to EMA / cyclophosphamide and vincristine chemotherapy and patients presenting with metastatic placental site trophoblastic tumors. - Newlands,E.S.; Mulholland,P.J.; Holden,L. (J Clin Oncol, 2000)