Allogeneic peripheral blood stem cell transplantation using a low toxicity conditioning regimen with fludarabine and busulfan for 13 patients with hematological malignancies

Objective To discuss the clinical effect of fludarabine and busulfan (Bu+Flu) as a low toxicity myeloablative conditioning regimen for allogeneic peripheral blood stem cell transplantation (allo- HSCT) in leukemia patients. Methods Clinical data of 13 patients with hematological malignancies receiving conditioning regimen with Bu+Flu for allo-HSCT were analyzed retrospectively. Conditioning regimen was Bu+Flu, compatriot mismatched and unrelated transplantation combined with rabbit anti-human thymocytes immune globulin (ATG). CsA+short course of methotrexate or CsA + mycophenolate mofetil were used to prevent graft-versus-host disease (GVHD). DNA sequencing of short tandem repeat (STR) polymorphism analysis method was performed for identification of donor stem cells implantation. Results 13 patients all tolerated with this conditioning regimen well, no serious complications occurred. Neutrophil engraftment was at 9-15 days (median 11 days), platelet engraftment at 8-25 days (median 13 days). 10 patients achieved hematopoiesis reconstitution with their full donor chimerisms confirmed by STR-DNA analysis. Acute GVHD occurred in 5 cases, accounting for 38.5%. Chronic GVHD occurred in 4 cases of 10 patients could be assessed, accounting for 40.0%. Severe GVHD more than II degree did not happen. 1-39 months (median time 11 months) of follow-up revealed the overall survival rate of 76.9%(10/13), disease-free survival of 61.5% (8/13). The causes for death were relapse in all. Conclusion The conditioning regimen with Bu+Flu has low toxicity, well tolerance and better effect.