Risk factors and implications of oral mucositis in recipients of allogeneic hematopoietic stem cell transplantation

Background: Oral mucositis (OM) is a common toxicity of stem cell transplantation (SCT). We sought to evaluate OM burden, risk factors, and implications in a cohort of allogeneic-SCT recipients. Methods: This was a single-center study including 115 adult allogeneic-SCT transplanted between 2016 and 2018 for various hematological conditions. Conditioning intensity was categorized as myeloablative (MAC, 39%), reduced intensity (34%), or reduced toxicity (RTC, 27%) in patients conditioned with fludarabine-treosulfan. OM was prospectively graded using the Common Terminology Criteria for Adverse Events (v.4.0) system. Results: Moderate-to-severe OM (grade 2-4) was experienced by 60% of patients. In a univariate analysis, younger age (P =.023), lower body mass index (P =.01), recent smoking (P =.08), recent antibiotics exposure (P =.018), MAC (P '.001), and methotrexate (P =.009) were associated with moderate-to-severe OM. In a multivariable logistic regression model, conditioning and graft-versus-host disease prophylaxis remained significant. OM risk was lowest with RTC (RTC vs MAC: odd ratio [OR] 0.05, P '.001), and recent antibiotic exposure trended toward increased risk (OR 1.88, P =.168). OM was associated with longer hospitalization, delayed neutrophil engraftment, and gastrointestinal-related infections. Conclusion: Oral mucositis remains a leading SCT complication. Treosulfan-based conditioning has low mucosal toxicity and is appealing given previous reports on its high efficacy.