BackgroundIn the absence of a HLA-matched related donor, allogeneic stem cell transplantation (allo-SCT) from unrelated donors or haploidentical donors are potential alternatives for patients with acute leukemia with an indication to allo-SCT.The objective of this study was to compare the outcomes of allo-SCT from T cell-repleted haploidentical donors (Haplo) with matched related donors (MRD) and unrelated donors, which include matched (MUD 10/10) or mismatched unrelated donor at a single HLA-locus (MMUD 9/10), for patients with acute leukemia.MethodsThis descriptive cohort study included patients with acute myeloid leukemia AML (n=66) and acute Lymphoblastic Leukemia ALL (n=111) that received allo-SCT between January 2015 and December 2018. The probabilities of overall survival (OS) at 100 days, 1 year and 3 years were calculated using the KaplanÐMeier method and log-Rank test (p<0.20). Chi-square test and fisher exact test was be applied to analyze relapse and graft-versus-host disease (GVHD) grade III-IV according to donors.Resultsone hundred seventy-seven patients received allogeneic transplant from MRD 42.9% (n=76), MUD/MMUD 28.8% (n=51), and Haplo donors 28.2% (n=50). Unrelated donors included 36 MUD and 15 MMUD. The median age was 33 years (range 16-67 years). Conditioning regimens were myeloablative for all patients. GVHD prophylaxis was post-transplantation Cyclophosphamide (Cy-Post) Tacrolimus (TAC) and mycophenolate Mofetil (MMF) for Haplo, Anti-Thymocyte globuline (ATG) and Methotrexate (MTX) for MRD/MMUD and Cyclosporine and MMF for MRD. Median follow-up was 409 days (minimum: 12 Ð maximum: 1724). The cumulative relapse incidence (RI) was not significantly different between Haplo, MUD/MMUD and MRD: 22%, 17%, and 25%, respectively (p = 0.619). The percentage of grades IIIÐIV aGvHD was superior for MRD 23,7% compared to MUD/MMUD 7,8% and Haplo 12.8% (p=0,044); This finding could be related with differences in GVHD phrophylaxis protocols. The 100 days, 1year and 2 years OS were 93.4%,82.3%, 72% (p=0.003); 72.3%, 66.6%, 54% (p=0.05) and 67,1%,60.7%, 42% (p=0.008) for MRD, MUD/MMUD and Haplo respectively (Figure 1 Ð 3).ConclusionsIn this study Allo-HSC from haplo Donors was associated with inferior 100 days, 2 and 3 years OS compared with MUD/MMUD and MRD. In the absence of a HLA-matched related donor, allogeneic stem cell transplantation (allo-SCT) from unrelated donors or haploidentical donors are potential alternatives for patients with acute leukemia with an indication to allo-SCT. The objective of this study was to compare the outcomes of allo-SCT from T cell-repleted haploidentical donors (Haplo) with matched related donors (MRD) and unrelated donors, which include matched (MUD 10/10) or mismatched unrelated donor at a single HLA-locus (MMUD 9/10), for patients with acute leukemia. This descriptive cohort study included patients with acute myeloid leukemia AML (n=66) and acute Lymphoblastic Leukemia ALL (n=111) that received allo-SCT between January 2015 and December 2018. The probabilities of overall survival (OS) at 100 days, 1 year and 3 years were calculated using the KaplanÐMeier method and log-Rank test (p<0.20). Chi-square test and fisher exact test was be applied to analyze relapse and graft-versus-host disease (GVHD) grade III-IV according to donors. one hundred seventy-seven patients received allogeneic transplant from MRD 42.9% (n=76), MUD/MMUD 28.8% (n=51), and Haplo donors 28.2% (n=50). Unrelated donors included 36 MUD and 15 MMUD. The median age was 33 years (range 16-67 years). Conditioning regimens were myeloablative for all patients. GVHD prophylaxis was post-transplantation Cyclophosphamide (Cy-Post) Tacrolimus (TAC) and mycophenolate Mofetil (MMF) for Haplo, Anti-Thymocyte globuline (ATG) and Methotrexate (MTX) for MRD/MMUD and Cyclosporine and MMF for MRD. Median follow-up was 409 days (minimum: 12 Ð maximum: 1724). The cumulative relapse incidence (RI) was not significantly different between Haplo, MUD/MMUD and MRD: 22%, 17%, and 25%, respectively (p = 0.619). The percentage of grades IIIÐIV aGvHD was superior for MRD 23,7% compared to MUD/MMUD 7,8% and Haplo 12.8% (p=0,044); This finding could be related with differences in GVHD phrophylaxis protocols. The 100 days, 1year and 2 years OS were 93.4%,82.3%, 72% (p=0.003); 72.3%, 66.6%, 54% (p=0.05) and 67,1%,60.7%, 42% (p=0.008) for MRD, MUD/MMUD and Haplo respectively (Figure 1 Ð 3). In this study Allo-HSC from haplo Donors was associated with inferior 100 days, 2 and 3 years OS compared with MUD/MMUD and MRD.