Haploidentical Hematopoietic Stem Cell Transplantation In Hematologic Malignancies with G-CSF Mobilized Bone Marrow Plus Peripheral Blood Stem Cells Grafts without T Cell Depletion: a Single Center Report of 29 Cases

Haploidentical Hematopoietic stem cell transplantation (Haplo-HSCT) has provided an alternative option since virtually all patients have an immediately available donor. In order to reduce the occurrence of severe acute GVHD, initially we used donor bone marrow with G-CSF mobilization as hematopoietic stem cell source and achieved good effect. However, as this work carried out widely, it is difficult to collect enough bone marrow cells from donor due to the much differences body weight between the recipient and donor, and lead to patients with hematopoietic recovery slowly. From February 2003 we started trying to use bone marrow and peripheral blood stem cell as stem cell source.

Twenty-nine patients with hematologic malignancies were enrolled in this study between February 2003 and August 2007 at the general hospital of air force. Conditioning regimen consisting of high-doses of cytarabine and cyclophosphamide with total body irradiation, while 6 cases were preconditioned with busulfan, cytarabine and cyclophosphamide. aGVHD was prevented by a combination of immunosuppressive drugs including a monoclonal antibody against human CD25 (basiliximab), cyclosporine A (CsA), methotrexate (MTX), mycophenolate mofetil (MMF), and a rabbit anti-thymocyte globulin. Donors were given G-CSF at a dose of 300μg daily for 6 consecutive days prior to marrow harvesting. Peripheral blood stem cell was collected on the 7th day.

All patients attained successful neutrophil and platelet recovery. The median time to neutrophil engraftment was 17.1days, and that of platelet recovery was 20.9 days. The incidence of grade II-‡W GVHD was 31.03% and grade III-‡W GVHD was 13.79%. The GVHD-related death was 3.45%. The incidence of cGVHD was 48.2%. The incidence of extensive cGVHD was 23.3%. The incidence of diseases relapsed was 13.79%. A median follow-up of 54 months noted that 13 patients died, while 16 survived. The total disease-free survival rate longer than 3 years was 55%.

G-CSF mobilization bone marrow and peripheral blood stem cell as stem cell source for Haplo-HSCT provided rapid and sustained engraftment without increase of severity GVHD. The rate of disease relapse was reduced. This treatment was particularly suitable for patients with heavier weight.

No relevant conflicts of interest to declare.