Decitabine Plus mBU/CY for High Risk Acute Leukemia With MRD Pre-HSCT

Patients enrolled in this study would receive decitabine 200mg·m-2·d-1 on day -12 and -11 pre-HSCT. The conditioning therapy for human leukocyte antigen (HLA)-mismatched HSCT patients was modified BU/CY plus ATG (thymoglobulin; Sang Stat, France) consisting of cytarabine (Ara-C 4 g·m-2·d-1) intravenously on days -10 to -9, busulfan (BU 3.2 mg·kg-1·d-1) intravenously on days -8 to -6, cyclophosphamide (CY 1.8 g·m-2·d-1), intravenously on days -5 to -4, semustine (Me-CCNU, 250 mg·m-2), orally once on day -3, and ATG (2.5 mg·kg-1·d-1) intravenously on days -5 to -2. In matched sibling transplantations, patients received hydroxycarbamide (80 mg·kg-1) orally on day -10 and a lower dose of Ara-C (2 g·m-2·d-1) on day -9, but otherwise an identical regimen to the HLA-mismatched patients without ATG.

BM samples from patients were obtained to assess leukemia status after HSCT. The time points that we monitored BM samples included at time of allo-HSCT; 1 month, 2 months, 3 months, 4.5 months, 6 months, 9 months, and 12 months after allo-HSCT; and every 6 months thereafter to the defined endpoints or for at least until 5 years after transplantation.

Inclusion criteria

• acute leukemia patients with MLL-r,TLS-ERG,or SIL-TAL1,whose minimal residual disease were detectable pre-HSCT

Exclusion criteria

• pregnancy women
• uncontrolled severe infection