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Updated: May 17, 2026

Comprehensive Evaluation of the Effectiveness and Safety of Placenta-Targeted Drug Delivery Using Three Complementary Methods
Published on: September 10, 2018
Methotrexate on a 21-day cycle for low-risk gestational trophoblastic neoplasia
Juan Diaz1, M Bijoy Thomas, Charlotte Paz-Pabon
1Department of Obstetrics, Gynecology and Reproductive Sciences, Temple University Hospital, Philadelphia, PA 19140, USA.
Objective:
To perform an outcome analysis of patients with low-risk gestational trophoblastic neoplasia (GTN) treated with a 5-day intramuscular methotrexate (MTX) regimen on a 21-day cycle.
Study Design:
A retrospective review of 31 patients with low-risk GTN treated with a 5-day MTX regimen.
Results:
A total of 31 patients with low-risk GTN (WHO score < 7) received single-agent MTX at a dose of 0.4 mg/kg daily for 5 days every 21 days (mean number of cycles, 3; 83% remission). The only significant toxicity encountered was grade 2 stomatitis in 8 (26%) patients.
Conclusion:
A 5-day MTX regimen given every 21 days is convenient, well-tolerated and effective for patients with low-risk GTN.
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