Abstract
Post-transplant lymphoproliferative disease (PTLD) is a life-threatening complication of hematopoietic stem cell transplantation caused by Epstein-Barr virus (EBV) reactivation due to immunosuppression. Frontline treatment includes the reduction of immunosuppressive therapy and administration of rituximab. However, the incidence of EBV-related PTLD (EBV(+) PTLD) continues to increase, and patient prognosis remains poor. In this retrospective study, we designed an exploratory treatment strategy for PTLD using designated reduced-dose donor lymphocyte infusion (DLI) (CD3 + T cells: 5 × 10(4)/kg) for majority patients (11/14). We further analyzed the data of 27 patients with PTLD who underwent transplantation at our institutions. Our therapeutic strategy effectively treated PTLD. In this study, the DLI cohort demonstrated higher overall response and complete remission rates than rituximab monotherapy after two-week intervention. Additionally, the DLI group had a markedly higher 1-year overall survival (OS) than the rituximab group. Similarly, the reduced-dosage DLI group had a significantly higher 1-year OS than the conventional-dosage group. These results indicate that varied treatments (rituximab vs DLI) and DLI dosages (conventional vs reduced) had significant impact on OS. Finally, the reduced-dosage DLI group had a lower risk of non-relapse mortality and acute graft versus host disease than the conventional-dosage group. This study demonstrates that reduced-dosage DLI is a promising treatment for EBV(+) PTLD.