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Abstract Acute myeloid leukemia (AML) is characterized by an increase in the number of myeloid cells in the marrow and an arrest in their maturation, frequently resulting in hematopoietic insufficiency (granulocytopenia, thrombocytopenia, or anemia) with or without leukocytosis. Allogeneic and Autologous HSCT have been an established option for consolidation for more than two decades. Prospective randomized trials have not shown auto graft to be superior to chemotherapy but it is an effective approach. Allografting produces the best antileukemic effect of any treatment in any risk or age subgroup.There is general consensus that patients who have good risk disease do not require transplantation and patients with poor risk disease do benefit even though the post transplant survival is still only 30% to 40%. The debate focuses on the 60% of patients who have intermediate risk disease. G-CSF-mobilized PBSC are increasingly used instead of BM cells for G-CSF-mobilized PBSC are increasingly used instead of BM cells for allogeneic transplantation because they provide faster engraftment and better survival in recipients with poor-risk disease. Important difference among the sources of stem cell is the amount of mature T cells present. PBSC usually contains a lot more mature T cells compared to BM, which in turn contains more T cells compared to CB, and this partly explains the differences in the risk of graft rejection and graft-versushost disease (GVHD). Depletion of T cells is associated with increased risk of graft rejection and disease relapse, but lower risk of GVHD. One of the main reasons for preferring PSC worldwide is the important advantages provided by this method to the donor. These advantages are avoidance of anesthesia, lack of the need for hospitalization or blood transfusion, and very low serious adverse event risk. Most of the randomized controlled trials (RCTs) comparing matched related donor BM and PBSC transplantation for patients with hematological malignancies found no significant differences between the two stem cell source in important outcomes including overall survival, disease-free survival, transplant-related mortality, relapse, acute GVHD and chronic GVHD. However, all trials showed significantly faster neutrophil engraftment in PBSC transplants, and all but one trial showed significantly faster platelet engraftment in PBSC transplants, which may result in earlier hospital discharge for PBSC recipients and lower cost for PBSC transplantation. Lymphocyte recovery was also found to be better in the PBSC group in one trial.Some trials showed PBSC recipients had significantly more grade 2-4 acute GVHD, chronic GVHD and extensive chronic GVHD compared with BM recipients, which resulted in significantly more patients who underwent PBPC transplant needed immunosuppressive treatment, and longer periods of corticosteroid use and hospitalization. There was no difference in performance status, return to work, incidence of bronchiolitis obliterans, hematopoietic function, and secondary malignancies between the two groups in the long term in one trial. In contrast, another trial showed that late mortality due to chronic GVHD was more frequent in PBSC recipients compared with BM recipients. The number of peripheral-blood stem cells is estimated with use of the cell-surface molecule CD34 as a surrogate marker. The number of CD34+ cells in blood can be increased by mobilizing them from the marrow with granulocyte colonystimulating factor (G-CSF), which causes the proliferation of neutrophils and the release of proteases. Proteases degrade the proteins that anchor the stem cells to the marrow stroma and, together with protease-independent mechanisms, free the cells to enter the circulation. In out study we have found that there was a significant relationship between CD34+ cell count and engraftment of platelets till it reaches 100000 and there wasn’t a significant relationship with incidence of cGVHD. |