[Allogeneic hematopoietic stem cell transplantation for high-risk acute leukemia]

To retrospectively analyze the results of a consecutive series of 90 refractory/relapsed acute leukemia (AL) patients receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT) in our center.

Of the 90 refractory/relapsed AL patients, 56 were male and 34 female, with a median age of 37 (13 - 59) years. Among them, 73 patients suffered from AL including 11 Ph+ acute lymphoid leukemia in first complete remission, 23 in second or greater complete remission, 39 in non-remission or relapse and 17 patients suffered from myelodysplastic syndrome (MDS-RAEB or RAEB-T) before transplant. Allo-HSCT from HLA identical siblings was performed for all the patients, of whom 27 received bone marrow transplantation (BMT), 30 peripheral blood stem cell transplantation (PBSCT) and 33 BMT + PBSCT. Eleven patients underwent allo-HSCT with conditioning regimen of CY/TBI and 79 with BU/CY. CsA + MTX regimen was use for prophylaxis of graft-versus-host disease (GVHD). The average follow-up was 15 months.

At the last follow-up, 56/90 (62.2%) survived, 50/90 (55.5%) survived without leukemia and 28/90 (31.1%) relapsed. The estimated 4-year overall survival (OS) and disease-free survival (DFS) of the 90 cases was 45.5% and 34.9%. The 4-year OS and DFS were significantly higher for patients in CR (54.0%) or MDS (70.1%) than in non-remission and relapsed (28.2%) patients before allo-HSCT (P = 0.027). The outcome of grade 0-I acute GVHD was better than that of II-IV GVHD (57.6% vs 26.7%, P = 0.015). Sex, age, central nervous system leukemia, conditioning regimen and the source of stem cell were not the factors affecting OS, DFS, cumulative incidences of relapse rate and treatment related mortality. Multivariate analysis showed the most significant factor associated with high DFS was the disease state.

allo-HSCT can cure a significant proportion of refractory/relapsed AL patients, especially for those in CR. Early allo-HSCT is recommended for MDS patients.