Haploidentical (HAPLO) Vs Umbilical Cord Blood (UCB) Allogeneic Hematopoieitc Cell Transplant (ALLO-HCT) in Patients ≥ 60 Years with Hematological Malignancies.

Introduction Allo HCT is a curative option for many aggressive hematological malignancies that increase with age. HAPLO donors and UCB are alternative sources of hematopietic cells for patients lacking a matched sibling or unrelated donor. The choice between UCB and HAPLO HCT is challenging as there is no direct comparison between the two. Objectives The goal of this study is to compare outcomes of UCB vs HAPLO HCT in patients ≥ 60 years who received an allo-HCT at UMass Memorial Medical Center over the past 5 years. Methods We retrospectively analyzed data of all patients ≥ 60 years who underwent allo-HCT with either HAPLO or UCB between June 2013 – June 2018. Patient characteristics were collected from the electronic medical records. We assessed rates of neutrophil and platelet engraftment, length of hospitalization, rates of acute (a) and chronic (c) graft vs host disease (GVHD), relapse rates, as well as day 100 and 1 year nonrelapse mortality (NRM) and overall survival (OS) rates. Results Tables 1 & 2 summarize patient characteristics and HCT outcomes. 22 patients were identified from the database. All patients received RIC with Thiotepa/Fludarabine/Melphalan with the exception of 1 UCB patient who received Fludarabine/Cyclophosphamide. UCB patients received GVHD prophylaxis with tacrolimus/mycophenolate/antithymocyte globulin (ATG). HAPLO cohort received GVHD prophylaxis with post-transplant cyclophosphamide (PTCy) plus tacrolimus/sirolimus/ATG. Conclusion Despite the higher HCT-CI/age in the HAPLO group, its day-100 NRM rate was lower. Although day 100 OS was superior in HAPLO, the 1-year OS rate was similar in both cohorts. The use of PTCy in HAPLO GVHD prophylaxis may explain the higher relapse rate. Length of hospitalization is markedly shorter for HAPLO, which may translate into lower HCT cost. These results need to be validated in a prospective randomized trial. UCB and HAPLO HCT are both feasible in patients ≥ 60 years. The choice should rely on the urgency of HCT, available cell dose and the expertise of the HCT center. [ABSTRACT FROM AUTHOR]