[Efficacies of hematopoietic stem cell transplantation for severe aplastic anemia: a report of 43 patients].

OBJECTIVE

To evaluate the efficacies of hematopoietic stem cell transplantation (HSCT) for severe aplastic anemia (SAA).

METHODS

A total of 43 SAA patients (SAA-I, n = 29; SAA-II, n = 14) underwent HSCT from 2002 January to 2013 December. There were 22 males and 21 females with a median age of 31 (12-49) years. And 35 patients received HLA-matched sibling HSCT (Sib-HSCT) while another 8 had unrelated donor HSCT (UD-HSCT). The hematopoietic stem cells were collected from bone marrow (n = 10), peripheral blood (n = 23) and bone marrow & peripheral blood (n = 10). Conditioning regimens were mostly composed of Fludarabine, antihuman thymocyte gloBulin and cyclophosphamide. Cyclosporine and methotrexate (including mycophenolate mofetil for UD) were offered for preventing graft-versus-host disease (GVHD). The median counts of mononuclear cell and CD34(+) stem cell were 8.1 (2.4-13.5) ×10(8)/kg and 3.7 (2.3-14.7) ×10(6)/kg respectively.

RESULTS

Hematopoiesis reconstitution was achieved in 42 patients. The median periods for neutrophils to 0.5×10(9)/L and platelets to 20×10(9)/L were +10 (+8-+25) days and +14 (+8-+80) days respectively. The median of survival time was not reached. Overall survival (OS) and failure-free survival (FFS) at 5 years had no differences between UD-HSCT and Sib-HSCT groups (OS: 87.6% vs 84.5%, P = 0.87; FFS: 86.2% vs 79.5%, P = 0.64). The same results also were seen between age ≤ 20 group and > 20 group (OS: 92.0% vs 82.5%, P = 0.39; FFS: 91.0% vs 77.3%, P = 0.38). The median follow-up time was 17.0 (0.4-140.0) months. And 8/43 patients died from thrombotic microangiopathy (TMA) (n = 1), TMA associated with capillary leak syndrome (n = 1), pulmonary infection (n = 3), acute GVHD of grade IV (n = 1) and unknown causes (n = 2).

CONCLUSIONS

Sib-HSCT is preferred for SAA patients under 40 years. Searching of HLA-matched unrelated donor should be performed soon after diagnosis if HLA-matched sibling is unavailable.