Comparison of treatment for low-risk GTN with standard 8-day MTX/FA regimen versus modified MTX/FA regimen without chemotherapy on the weekend

To compare the outcomes of patients with low-risk gestational trophoblastic neoplasia (GTN) treated with standard 8-day methotrexate/folinic acid (MTX/FA) versus modified regimen.Retrospective cohort study of patients with low-risk GTN followed at Rio de Janeiro Federal University, from January/1990-December/2017 with standard 8-day MTX/FA or modified regimen (MTX administered on the 8th day rather than 7th) to avoid treatment on the weekend.From 937 patients with low-risk GTN, 538 were treated with standard MTX/FA and 98 patients received modified regimen. Both groups were comparable in age (p = .749), antecedent pregnancy (p = .221), time to initiate chemotherapy (p = .926), hCG pretreatment level (p = .112) and WHO/FIGO prognostic risk score (p = .723). Patients treated with modified MTX/FA had twice of cases of metastatic lung disease compared with the standard regimen (22.5% vs 10.6%; p = .002). The rate of remission (p = .999), number of cycles to remission in the first-line (p = .966), chemoresistance (p = .500), time to switch to second-line therapy (p = .176), need for multiagent chemotherapy (p = .084), relapse (p = .122) or death (p = .475) was the same for both MTX/FA regimen. However, although patients receiving modified MTX/FA required a higher total number of remission cycles (6 vs 5 cycles; p = .004) and longer time to remission (19 vs 16 weeks; p .001) when compared with the standard regimen, these variables showed no significant differences after multivariate logistic regression adjusted for lung metastasis.The modified 8-day MTX/FA regimen didn't compromise oncologic outcomes for women with low-risk GTN. This regimen appears to be an acceptable alternative to standard 8-day MTX/FA when treatment on weekend isn't an option.