Objectives Low-risk gestational trophoblastic neoplasia (GTN) with WHO prognostic score of 0 to 6 has high cure rate. The aim of the study was to evaluate the effectiveness of single-dose methotrexate infusion in women with low-risk GTN.

Methods In this single centre retrospective cohort study, 115 women with low-risk GTN were treated between January 2000 and October 2019 with an intravenous bolus of 100 mg/m² of methotrexate followed by a 12-hour infusion of 200 mg/m². Serum human chorionic gonadotropin (hCG) levels were monitored weekly. If the hCG level dropped by 10-fold after 2 weeks, no further chemotherapy was given. Otherwise, chemotherapy was continued 2-weekly until 3 cycles post-normalisation of hCG. Characteristics between the 2 groups with or without complete remission with this regimen were compared.

Results All 115 women with low-risk GTN were cured. The overall complete remission rate with methotrexate was 85.2%, with 60.9% of women requiring a single-dose of methotrexate alone, and 24.3% requiring continuation of chemotherapy with 2-weekly methotrexate. 14.8% of women had unsatisfactory response with methotrexate alone and were cured with combination of methotrexate and actinomycin-D. The pre-treatment hCG levels were significantly lower in women who were cured with single-dose methotrexate regimen compared to those who failed this regimen (median hCG 1227 versus 3335 IU/L; P = 0.037).

Conclusions Single-dose methotrexate regimen offers an effective option for women with low-risk GTN and a low pre-treatment hCG level.