Autologous Hematopoietic Stem Cell Transplantationfor Adult with Acute Leukemia in First Complete Remission

Objective The objective of this study was to evaluate the clinical outcome of autologous hematopoietic stem cell transplantation (AHSCT) for acute leukemia(AL).

Methods The outcome of 56 AL patients who received autologous HSCT(AHSCT) for AL in first complete remission (CR) from May 2001 to May 2008 were analyzed retrospectively. There were 31 males and 25 females, the median age was 25(11~ 57)years. The diagnosis of these patients were acute myeloid leukemia (AML, n=38), acute lymphocytic leukemia(ALL, n=17) and acute hybrid leukemia (AHL, n=1). Patients were divided into low/moderate risk group (n=46) and high risk group (n=10) according to their characteristics of newly diagnosis. If the patient achieved first complete remission(CR), one to three courses of intensification chemotherapy containing high dose cytarabine(HDAC)were given. All the patients were in CR1 before AHSCT. Stem cells were mobilized with MAG regimen which composed of HDAC, Mitoxantrone and G-CSF. The conditioning regimen consisted of modified BU/ CY for AML patients or total body irradiation (TBI) plus cyclophosphamide (CTX) for ALL patients. Patients received consolidation chemotherapy every 3 months after AHSCT until 3 years post transplant. Nine patients received several course of cytokine-induced killer (CIK) cells treatment.

Result The median number of MNC and CD34 positive cell was 6.9(1.2 `21)×10<sup>8</sup>/kg and 2.3(1.6 `6.3)×10⁶/kg respectively. All patients achieved hemopoietc recovery. The median time of the engraftment of neutrophil and platelet was 9.7(8 `14) days and 12.9(9 `20) days posttransplant respectively. The incidence and severity of regimen-related toxicity were mild. The incidence of treatment related mortality (TRM)is 0%. The median follow-up of surviving patients was 31 months(range, 2 `86). Until now 46 patients are still alive, including 4 relapse cases. 13 cases were died of relapse. The five-year overall survival(OS) and the leukemia-free survival(LFS) were 77.3% and 71.9% respectively. The incidence of relapse was 23.2%. The OS and LFS in the low /moderate risk and high risk AL cohorts were 85.7%versus 40% and 79%versus 40% respectively(P<0.01)

Conclusion AHSCT is the first option for the AL patients who were in good or moderate risk group and had achieved first complete remission. Regular consolidation chemotherapy after transplantation was beneficial to improve the LFS of AL patients.