Comparing the risk of severe oral mucositis associated with methotrexate as graft-versus host-disease prophylaxis to other immunosuppressive prophylactic agents in hematopoietic cell transplantation: a systematic review and meta-analysis.

Purpose: This study examines the risk of severe oral mucositis (SOM) in graft-versus-host disease prophylaxis (GVHD) compared to other agents in hematopoietic cell transplantation patients.

Methods: A comprehensive search of four databases, including PubMed, Embassy, Web of Science, and Scopus, was conducted to identify studies reporting frequency and severity of oral mucositis in association with GVHD prophylactic regimens. RevMan 5.4 was used to perform the meta-analysis. Risk of bias assessment was carried out using the Rob-2 tool for randomized clinical trials (RCTs) and ROBINS-I tool for observational studies.

Results: Twenty-five papers, including 11 RCTs and 14 observational studies, met the inclusion criteria. The pooled results from eight RCTs showed a higher risk of SOM in patients receiving MTX or MTX-inclusive GVHD prophylaxis versus non-MTX alternatives (RR = 1.50, 95% CI [1.20, 1.87], I = 36%, P = 0.0003). Mycophenolate mofetil (MMF) and post-transplant cyclophosphamide (Pt-Cy) consistently showed lower risk of mucositis than MTX. Folinic acid (FA) rescue and mini-dosing of MTX were associated with reduced oral mucositis severity.

Conclusion: Patients receiving MTX have a higher SOM risk compared to other approaches to prevent GVHD, which should be considered in patient care. When appropriate, MMF, FA, and a mini-dose of MTX may be an alternative that is associated with less SOM. This work also underlines the scarcity of RCTs on MTX interventions to provide the best evidence-based recommendations.