Patients with refractory and relapse lymphoblastic leukemia had poor outcome even with marrow ablative conditioning mostly standard iv-Bu-Cy or Cy-TBI. In this study, we focus on a new treatment strategy with high-dose chemotherapy regimen consisting of fludaraibine+cytarabine+cyclophosphamide+etoposide followed by reduced intensity condiotning regimen consisting of fludarabine, busulfan and post-infusion cyclophophamide.

All patients with refractory and relapse lymphoblastic leukemia will receive a high-dose chemotherapy regimen consisting of fludaraibine+cytarabine+ cyclophosphamide+etoposide. At day 7 after chemo, a bone marrow aspiration and MRD study by flow-cytometry is planned. For those patients with no residual blasts will undergo allogeneic stem cell transplantation with reduced intensity condiotning regimen consisting of 5-day fludarabine and 3-day busulfan and post-infusion cyclophophamide (D+3 and +4) as GVHD prophylaxis.

Inclusion Criteria:

• adult patients with refractory or relapse acute lymphoblastic leukemia not in remission after 2 cycles of induction chemotherapy early relapse (1st remission less than 6 months) not in remission after 1 cycle of re-induction chemotherapy multiple relapse
• age 16-60 years with inform consent
• no contraindication for allogeneic transplantation: active infection, allergy to FLu/Bu/CTX, liver and renal function damage
• HLA matched related (6/6), unrelated donors (8~10/10) or haplo

Exclusion Criteria:

• liver function/renal function damage (over 2 X upper normal range)
• mental disease