Objective: To evaluate the efficacy and optimize the timing of allogeneic hematopoietic stem cell transplantation (allo-HSCT) from human leukocyte antigen (HLA)-identical siblings for myelodysplastic syndrome (MDS).
Methods: From January 2003 to December 2012, 95 patients with MDS or secondary acute myeloid leukemia (AML) were treated with HLA-identical allo-HSCT in our hospital. The median age was 43 (21-59) years. Conditioning regimens including modified busulfan (Bu)/cyclophosphamide (Cy) or Bu/ fludarabine (Flu) were used. All patients received transfusion of donor stem cells mobilized by granulocyte colony-stimulating factor (G-CSF) from bone marrow and/or peripheral blood. Eleven patients had refractory anemia (RA) or RA with ringed sideroblasts, 53 of RA with excess blasts (RAEB), 15 of RAEB in transformation (RAEB-t), and 16 progressing to secondary AML.
Results: A total of 93 patients achieved sustained myeloid engraftment. The cumulative incidence of grade II-IV acute graft versus host disease (aGVHD) was 12.9% ± 3.5%. The 3-year cumulative incidence of chronic graft versus host disease (cGVHD) was 80.3% ± 4.9%. After a median follow-up of 28.7 months, 29 patients died. The 3-year estimated overall survival (OS) and disease-free survival (DFS) rates were 69.9% ± 5.0% and 58.0% ± 5.4% respectively. The cumulative relapse rate (RR) was 25.9% ± 4.7%, while non-relapse mortality (NRM) was 16.1% ± 4.0%. Multivariate analyses showed that non II-IV aGVHD and cGVHD were favorable factors associated with OS. Low DFS rate was correlated with high scores of international prognostic scoring system (IPSS). Patients with RAEB-t and AML (n = 31) were divided into 3 groups: no chemotherapy before HSCT (Group 1), chemotherapy but not achieving remission (Group 2) and chemotherapy and achieving remission (Group 3). The 3-year OS rate was 100.0% in Group 3, which was significantly higher than those of Groups 1 and 2 with 33.9%, 32.7% respectively (P < 0.05). The difference of DFS and RR in the three groups did not reach statistic difference.
Conclusions: Allo-HSCT from HLA-identical siblings is effective for patients with MDS. IPSS is of prognostic value for post-transplantation outcome. For patients with progressive disease before transplantation, maximal control of blasts in bone marrow may improve the prognosis of advanced MDS.