Posttransplant lymphoproliferative disorders in transplant recipients

Posttransplant lymphoproliferative disorder (PTLD) is a serious complication of organ transplantation, with a reported incidence between 0.8% and 32%. The incidence of PTLD mainly depends on the transplanted organ, the immunosuppressive drugs, the viral serology, and the age of the recipient. The aim of our study was to analyze our patients diagnosed with PTLD. Among 1040 transplantations, including 931 renal, 14 heart, 55 liver and 40 allogeneic peripheral blood stern cell (PBSC), 8 patients (7 male, I female) were diagnosed with PTLD. Five patients had undergone renal, one cardiac, one liver, and one PBSC transplantations. Four patients were diagnosed within the first year of transplantation. Six patients presented with abdominal disease, one with convulsions, and one with peripheral lymph node involvement. According to the World Health Organization classification system, six patients were diagnosed as diffuse large B-cell lymphoma, one patient Burkitt's lymphoma, and one polymorphic PTLD. At the time of diagnosis, 7 patients showed positive Epstein-Barr virus (EBV) and cytomegalovirus (CMV) Ig G and negative Ig M; one patient, positive EBV Ig M and negative CMV Ig G and M. EBV viral load was extremely high in the plasma of two patients by polymerase chain reaction. One of these patient's pathologic tissue revealed positive EBV DNA, which was not detected in six of the other eight patients. This patient was an 8-year-old boy diagnosed with Burkitt's lymphoma at 31 months after liver transplantation. Seven patients died of disease or complications of chemotherapy. Only one patient survived after the diagnosis of PTLD. In conclusion, even with treatment the mortality rate was high among our patients with PTLD. To decrease the incidence of PTLD and related mortality, risk factors must be evaluated in multicenter studies.