Role of Antithymocyte Globulin and Granulocyte-Colony Stimulating Factor-Mobilized Bone Marrow in Allogeneic Transplantation for Patients with Hematologic Malignancies

The main obstacle for allogeneic transplantation is delayed hematologic reconstitution and serious graft-versus-host disease (GVHD). The results of 128 patients with hematologic malignancies undergoing HLA-identical (n = 52) or HLA-haploidentical/mismatched (n = 76) hematopoietic stem cell transplantation (HSCT) performed during the same time period were compared. Patients with HLA-identical HSCT received unmanipulated granulocyte-colony stimulating factor-mobilized peripheral blood stem cells (G-PBSCs). Forty-six patients with HLA-haploidentical related HSCT received antithymocyte globulin (ATG) in conditioning regimens followed by the transplantation of the combination of unmanipulated G-PBSCs and granulocyte-colony stimulating factor-mobilized bone marrow (G-BM) and 30 patients with HLA-mismatched unrelated HSCT received ATG in conditioning regimens followed by the transplantation of unmanipulated G-PBSCs. All patients got successful hematopoietic engraftment. The cumulative incidences of grades I to II acute GVHD (aGVHD) on day 100 in the identical, haploidentical related and mismatched unrelated cohorts were 21.2%, 43.5%, and 53.3%, respectively. The cumulative incidences of chronic GVHD (cGVHD) in the identical, mismatched unrelated, and haploidentical related cohorts were 34.6%, 33.3%, and 10.9%, respectively. The 2-year relapse and treatment-related mortality (TRM) rates were 19.2%, 23.9%, 23.3%, and 9.6%, 8.7%, 10% for patients who underwent identical, HLA-haploidentical related, and mismatched unrelated transplantation, respectively. The 2-year probabilities of leukemia-free survival and overall survival were 72.2%, 70.6%, 68.1%, and 76.5%, 77.8%, 70.0% after identical, haploidentical related and mismatched unrelated transplantations, respectively. Multivariate analyses showed that only advanced disease stage and a diagnosis of disease had increased risk of relapse, treatment failure, and overall mortality. In conclusion, it is a feasible approach with acceptable outcomes for patients undergoing HLA-haploidentical related HSCT by the combination of G-PBSCs and G-BM with conditioning regimens including ATG.