Objective: To explore the therapeutic feasibility of allogeneic hematopoietic stem cell transplantation (allo-HSCT) from partially HLA-mismatched related donors for hematologic diseases.
Methods: Thirty patients with hematologic diseases received allo-HSCT from 1 - 3 loci mismatched related donors conditioning regimen consisting of ATG (thymoglobulin, total dose of 10 mg/kg, intravenously on - 4 d to - 1 d), and only 5 (18%) of 28 recipients from HLA-identical sibling donors were treated with regimen containing ATG. Donors were given G-CSF prior to hematopoietic stem cell harvest and CsA, short-term MTX and mycophenolate mofetil (MMF) were used for GVHD prophylaxis in both group.
Results: All patients were successfully engrafted. There was no significant difference in the incidence of grade II to IV acute graft-versus-host disease (aGVHD) and grade III to IV aGVHD between the mismatched and matched groups (34% vs 32%, and 13% vs 11%, respectively). 3-year overall survival (OS) and disease-free survival (DFS) in mismatched and matched groups were 57% vs 77% (P = 0.14) and 57% vs 69% (P = 0.28), respectively. Multivariate analysis showed that advanced disease pre-transplant (P = 0.006) and CMV infection (P = 0.04) were risk factors for OS. OS for patients with stable disease in mismatched and matched groups were 87% vs 81% (P = 0.65) respectively, and for those with advanced disease were 21% vs 71% (P = 0.02).
Conclusions: It is feasible to perform allo-HSCT from 1 -3 loci HLA-mismatched related donors for patients with stable disease who lack HLA-identical sibling donors. Nevertheless, for patients with advanced disease optimized conditioning regimen and intensive supporting therapy should be administered to obtain better clinical outcomes.