Abstract:

BACKGROUND: In allogene hematopoietic stem cell transplantation, the choice of preconditioning scheme is an important link of the success of hematopoietic stem cell transplantation, and a major research direction of stem cell transplantation. The myeloablative pretreatment scheme has great toxicity, and pretreatment related death rate is high. Thus, it is necessary to explore an ideal pretreatment scheme to expect a decrease in side effects and relapse.
OBJECTIVE: To observe the effect of modified Bu/CY pretreatment regimen for treating hematologic malignancies.
METHODS: The 8 patients were selected at the Department of Hematology, Haikou Municipal People’s Hospital Affiliated to Xiangya School of Medicine, Central South University from November 2003 to March 2008, and received modified Bu/CY pretreatment: cytarabine 2.0-3.0 g/(m²•d)× 2 d, intravenous drip, for 24 consecutive hours; myleran 4 mg/(kg•d)× 3 d; cyclophosphamide 50 mg/(kg•d)× 2 d; methyl-cyclohexyl nitrosourea 25 mg/(m²•d)×1 d; antithymocyte globulin 25 mg/(kg•d)× 4 d. We have increased the arabinosylcytosin dose twice, and changed to a 24-hour infusion via intravenous drip, so that pretreatment strength was increased and promote lasting implantation of hematopoietic stem cells, based on the modified program. Graft-versus-host disease (GVHD) prevention: cyclosporin A and mycophenolate mofetil would be used advanced to minus 7 days (one day before stem cell transfusion is minus 1) based on the classic methotrexate regimen. The ABO blood group changes and DNA were tested in patients before and after transplantation.
RESULTS AND CONCLUSION:  ①The detection of hematopoietic reconstitution after transplantation: All patients have received hematopoietic reconstitution, with no pretreatment-related death. The white blood cells reduced to 0 after -3 - +7 days of hematopoietic stem cell transplantation, and continues to (3-22) days, +10 - +21 days white blood cells > 1.0×10⁹ /L, +11 - +51 days, platelets > 20×10⁹ /L. ②Incidence of GVHD: of 8 patients, there were GVHD Ⅳ grade (intestinal) in 1 case, acute graft-versus-host disease grade Ⅰ-Ⅱ in 3 cases. Above-mentioned results indicated that the further modification of BU/CTX2 regimen may be an effective pretreatment program, with a few side effects, which is better than the classic total-body irradiation/CY regimen. What’s more, it is simple accurate, reliable role of anti-leukemia and will be a safe and effective method for treating hematologic malignancies.