Haploidentical Peripheral Blood Stem Cell Transplantation (Haplo-PBSCT) with Cyclophosphamide Pos Transplant (CyPost) in High-Risk Hematologic Malignancies. Results of 5 Years in Transplant Center in Northeast of Mexico

Introduction: Haploidentical peripheral blood stem cell transplantation ( Haplo-PBSCT) is a curative option in patient with hematology malignancy. In Mexico is very difficult to find an identical HLA donor , for this reason Haplo PBSCT it is an option in our public Health institution. Materials and methods: we aimed a retrospective study since (2017 -2021) in our Hospital Unidad Médica de alta Especialidad 25, Instituto Mexicano del Seguro Social (IMSS UMAE 25) Monterrey, Mexico. We include patients over 15 years of age who were undergo Haplo PBSCT with hematolgy malignancies . We performed Analysis of Overall and Relapse-free survival with kaplan meier curves and incidence of acute and chronic graft versus host disease (GVHD) and percentage of Transplant-Related Mortality (TRM). Results: we analized a 38 patients, the median age was 35 years (range 15-64). Of the total , 25 were male (65%) and 13 famale (34%). The rest of baseline data is described in table 1. The median time of neutrophil engrafment was days 17 ( 11-26 ) and platelets was 19.5 days ( 12-38 ). The Incidence of Primary Graft failure was 18 % ( seven patients). Patients with graft had 99-100% chimerism at day 100. The Incidence of aGVHD was 26 % and the cGVHD was 16%. DLI was used in four patients to treat passenger lymphocyte syndrome (2 patients) and ( 2 patients) with severe graft rejection. The principal cause of death was sepsis in eleven patients (29%). Two patients with acute leukemia (AML and ALL) died after development of post transplant lymphoproliferative disease. The TRM was 28.2%. There were no relapse-related deaths during follow-up after Haplo-PBSCT. The median of survival was 4.5 months ( range 1-44) with Overall Survival (OS) of 42 % at 3 years ( figure 1). Conclusion: Our analysis shows results that were comparable with those published in first world international transplant centers . Relapse remains the major cause of transplant failure, in our population the antigenic disparity between donor and recipient can strengthen the immune response versus disease. Haplo-PBSCT is a feasible transplantation method in patients with hematological malignancies in developing countries with limited resources. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.