The relapse leukemia patients after transplantation were divided into two groups randomly. Group D1: patients received first-donor stem cells infusion(DSI) treatment with or without chemotherapy; group D2: patients received second-donor DSI treatment with or without chemotherapy. The second donors were preferably donors who were genetically related and had more HLA-match locus. The re-induction chemotherapy regimen was primarily MAT(mitoxantrone, cytarabine, Teniposide ) for acute myeloid leukemia (AML) and VMCLD(vincristine, Teniposide, cyclophosphamide, L-Asparaginase, Dexamethasone) for acute lymphocytic leukemia (ALL), and no graft versus host disease(GVHD) prevention was conducted pre- and post- therapy.

Evaluation indications include bone marrow morphology,hematopoietic recovery (neutrophil and platelet), 100-day transplantation-related mortality (TRM), donor chimerism, acute GVHD, chronic GVHD, disease free survival (DFS), and overall survival (OS). The cut-time of the follow-up was Oct, 2013. DFS was defined as the time between the date of transplantation to the death or relapse. OS was defined as the time from diagnosis to death or to the last date of follow-up until Oct. 2013.

Inclusion Criteria:

• Eligible patients were between 9 and 67 years of age with de novo diagnosed or treated-related Acute leukemia relapsed after HLA-matched hematological stem cell transplantation from Feb 2005 to Feb 2013
• Relapse was morphologically and molecularly diagnosed,with the help of cytogenetic and engraftment.
• Eastern Cooperative Oncology Group (ECOG) performance status was 0 to 2

Exclusion Criteria:

• Patients without receiving CR will not receive further post-remission trial therapy
• The patients of AML-M3 were excluded from this study.

Eligible patients were between 9 and 67 years of age with de novo diagnosed or treated-related Acute leukemia relapsed after HLA-matched hematological stem cell transplantation from Feb 2005 to Feb 2013.