ControlledEpstein–Barr virus reactivation after allogeneic transplantation is associated with improved survival

Abstract Epstein– B arr virus reactivation ( EBV ‐ R ) frequently occurs in patients having allogeneic hematopoietic stem cell transplantation ( HSCT ). We evaluated the impact of controlled EBV ‐ R on survival of 190 patients (114 M /76 F , median age: 51 yr, range 18–69), having HSCT for hematological malignancies (105 acute leukemias and myelodysplasias, 71 lymphoproliferative disorders, 14 others). Overall survival ( OS ) and progression‐free survival ( PFS ) were compared between patients with and without EBV ‐ R . Of 138, patients had reduced‐intensity conditioning regimen. Various stem cell sources (141 PB , 33 umbilical cord blood and 16 bone marrow) were used. Patients with EBV ‐ R had longer PFS and OS than those without EBV ‐ R : PFS at 2 yr 69% vs. 51% and at 5 yr 47% vs. 38% ( P < 0.04); OS at 2 yr 76% vs. 64% and at 5 yr 63% vs. 47%) ( P < 0.001). The use of rituximab had no impact on OS and PFS , but it reduced the intensity of GVHD , despite the fact that TRM was not significantly different between the two groups of patients. So, rituximab may have an additional effect to other factors on PFS and OS . In multivariate analysis, antithymocyte globulin administration was not a significant factor for PFS ( P = 0.68) and for OS ( P = 0.81). Circulating NK cells were significantly increased by 22% ( P = 0.03) in EBV ‐ R patients with no differences for other parameters. Controlled EBV ‐ R in the setting of HSCT is associated with better OS and PFS , with a significant increase in circulating NK cells.