Purpose: To evaluate the results of etoposide, methotrexate, and dactinomycin alternating with cyclophosphamide and vincristine (EMA/CO) chemotherapy in women with high-risk gestational trophoblastic tumors (GTT) and to document the middle- and long-term toxicity of the regimen.
Patients and methods: A total of 272 consecutive women with high-risk GTT, including 121 previously treated patients, were treated with weekly EMA/CO. The median follow-up duration is 4.5 years (range, 1 to 16).
Results: The cumulative 5-year survival rate is 86.2% (95% confidence interval, 81.9% to 90.5%). No deaths from GTT have occurred later than 2 years after the end [corrected] of EMA/CO. In a multivariate model, adverse prognostic factors were the presence of liver metastases (P < .0001), interval from antecedent pregnancy (P < .0001), brain metastases (P = .0008), and term delivery of antecedent pregnancy (P = .045). There were 11 (4%) early deaths, while 213 patients (78%) achieved a complete remission. Forty-seven (17%) developed drug resistance to EMA/CO, of whom 33 (70%) were salvaged by further cisplatin-based chemotherapy and surgery. Two women developed acute myeloid leukemia, two cervical malignancy, and one gastric adenocarcinoma after EMA/CO. More than half (56%) of the women who had fertility-conserving surgery and who have been in remission at least 2 years have become pregnant since the completion of EMA/CO, with 112 live births, including three infants with congenital abnormalities.
Conclusion: EMA/CO is an effective and well-tolerated regimen for high-risk GTT. More than half of the women will retain their fertility; however, there is a small but significant risk of second malignancy.