Epstein-Barr virus-associated post-transplant lymphoproliferative disord:rs (EBV-PTLD) occur in approximately 1% of allogeneic bone marrow transplant (BMT) patients, with higher risks reported after unrelated donor BMT, particularly with T i ell depletion. Umbilical cord blood (UCB) is being increasingly used for transplantation, jut the ability of neonatal T cells to regulate EBV-associated lymphoproliferation is unknown. As UCB transplantation (UCBT) is associated with relatively low infused donor T (ell dose, often greater donor-recipient HLA disparity and use of anti-thymocyte globi lin during conditioning, risk of EBV-PTLD after UCBT may be increased. To investigate he incidence of EBV-PTLD after UCBT we analyzed 263 unrelated donor UCB transplants performed from August 1993 to December 1999 at Duke and the University of Minnesc ta. Five cases of EBV-PTLD were identified with a cumulative incidence of 1 % (0-2) at 5 ye; rs. EBV-PTLD affected recipients aged 1 to 49 years (median 8), with 4 patients transplan ed for leukemia and one for immunodeficiency. Patients received UCB grafts which w :re HLA-matched (n=l), or mismatched at 1 (n=l) or 2 (n=3) HLA-loci. Diagnosis occured at 4-14 months (median 6) after UCBT, with one patient being diagnosed at autopsy. Notably, 4 of 5 patients had preceding grade II-IV acute GVHD. The pathology ranged from polymorphic to monomorphic morphology, with 4 patients having widely disseminated disease. Treatment of 4 patients consisted of withdrawal of immunosuppression and rituximab, with 1 patient receiving additional chemotherapy. Two of 4 patients responded and are alive with follow-up of 3.5 and 5 months, respective ly. In summary, despite a number of potential risk factors, the incidence of EBV-PTLD alter unrelated donor UCBT appears similar to that observed after transplantation using other allogeneic stem cell sources. Since adoptive immunotherapy with donor lymphocytes is not an available option for recipients of unrelated donor UCBT, new therapeutic strategies are needed for PTLD occurring in this setting, and rituximab appears promising.
|Original language||English (US)|
|Issue number||11 PART I|
|State||Published - Dec 1 2000|