[Clinical analysis of oral mucositis after secondary allogeneic hematopoietic stem cell transplantation in patients with hematological diseases]

Objective: This study aimed to investigate the clinical characteristics of oral mucositis (OM) in patients with hematological diseases who received secondary allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: This study retrospectively analyzed data on 58 patients with hematological diseases who underwent secondary allo-HSCT at the Peking University People's Hospital from January 2018 to December 2023. The control group included 116 randomized patients after primary allo-HSCT during this period (1:2 ratio) with matched gender, age, and diagnosis. The incidence of OM and overall survival (OS) were compared between the two groups. Results: The secondary allo-HSCT and control groups reported 17 (29.31%) and 16 (13.79%) cases that developed OM (P=0.014), whereas 10 (17.24%) and 7 (6.03%) developed grade ≥3 OM (P=0.019). The median time for OM to occur was 4 days (1-9 days) and 5 days (1-10 days) posttransplantation in the secondary allo-HSCT and control groups, respectively. The multivariate analysis revealed that the use of whole-body radiation therapy as the main pretreatment regimen was an independent risk factor for OM occurrence (P=0.019). Among patients with OM, an age of <55 years is a risk factor for developing grade 3-4 OM (P=0.028). All patients who underwent the secondary allo-HSCT received granulocyte implantation. The median time of granulocyte implantation in 17 patients with OM was 14 days posttransplantation, whereas the median time of granulocyte implantation in patients without OM was 12 days posttransplantation. The difference was not statistically significant (P=0.721). The presence of OM did not affect the occurrence of acute graft-versus-host disease (P=0.938). No statistically significant difference was observed in the 2-year OS rate between patients with and without OM during the secondary allo-HSCT (51.9% vs 50.4%, P=0.943). No statistically significant difference was observed in the 2-year OS rate between patients with OM undergoing the secondary allo-HSCT and those undergoing the primary allo-HSCT (51.9% vs 81.3%, P=0.185) . Conclusions: The proportion of patients with concurrent OM was significantly increased in the secondary allo-HSCT, and the severity was more severe. Whether or not to merge OM does not affect granulocyte implantation, acute graft-versus-host disease incidence, and 2-year OS rate.