Single-Agent Therapy for Low Risk Gestational Trophoblastic Neoplasia (LRGTN): A Preliminary Report on a Randomized Clinical Trial to Compare Pulse-Methotrexate versus Pulse-Dactinomycin

The efficacy of single-agent chemotherapy for patients with low risk gestational trophoblastic neoplasia (LRGTN) with methotrexate or dactinomycin is well established, but efforts continue to reduce the toxicity, the patients time and cost of treatment. In a randomized clinical trial, we evaluated and compared the efficacy, toxicity and cost effectiveness of pulse-methotrexate versus pulse-dactinomycin as single-agent therapy in LRGTN. Forty low risk GTN patients were randomly assigned to receive pulse-methotrexate (30 mg/m2 weekly intramuscularly) (20 cases) or pulse-dactinomycin (1.25 mg/m2 every two weeks intramuscularly) (20 cases). Treatment continued if no major toxicity was encountered and beta human chorionic gonadotropin (-hCG) values were lower than 5mIU/m2 in three consecutive weeks. Seventy percent of methotrexate group and 90% of dactinomycin group responded to treatment (100% remission was achieved with no recurrence in one-year follow-up). The mean time to response was 43 days for methotrexate and 66 days for dactinomycin group (P-value = 0.001). Patients achieved remission after receiving an average of 8 courses of therapy in methotrexate versus 6 courses in dactinomycin group (P-value = 0.002). The average cost of treatment per course was about 7 US$ for methotrexate and 62 US$ for dactinomycin group (P-value < 0.001). There were no cases of major toxicity in methotrexate or dactinomycin groups. Overall, both methotrexate and dactinomycin were associated with good remission rate. Based on our results, LRGTN treatment with dactinomycin is somewhat more effective than that with methotrexate, but methotrexate is more cost-effective for both patients and the health system. As the effectiveness of both pulse-methotrexate and pulse-dactinomycin does not differ significantly, pulse-dactinomycin is recommended as first-line treatment.