EPSTEIN-BARR VIRUS-ASSOCIATED POSTTRANSPLANT LYMPHO-PROLIFERATIVE DISEASE OF DONOR ORIGIN IN LIVER-TRANSPLANT RECIPIENTS

Background/Aims: Post-transplant lymphoproliferative disease, a potent ial complication of solid organ transplantation, occurs in about 3% of orthotopic liver transplant recipients, We report the genetic and vir ological characterization of two cases of posttransplant lymphoprolife rative disease that occurred early (4 and 6 months) after orthotopic l iver transplant as large-cell non-Hodgkin's lymphomas located at the h epatic hilum, Methods: Lymphomatous tissues were analyzed for clonalit y and presence of Epstein-Barr virus (EBV) sequences by Southern blot, polymerase chain reaction, and in situ hybridization techniques, Resu lts: The tumors in both cases were sustained by a clonal proliferation of B lymphocytes containing type A EBV DNA, Moreover, in situ hybridi zation with a digoxigenin-labeled EBV-specific probe evidenced a stron g nuclear signal in most of the neoplastic cells, DNA microsatellite a nalysis at three different loci detected alleles of donor origin in bo th tumor samples, suggesting that the neoplastic B cells were of donor origin, Conclusions: EBV-infected donor B lymphocytes might be respon sible for intragraft post-transplant lymphoproliferative disease in or thotopic liver transplant recipients. As 20 to 30% of post-transplant lymphomas involve the graft itself, donor-derived post-transplant lymp hoproliferative disease might be more frequent than presently apprecia ted, Prospective studies are needed to assess its real incidence and i dentify possible risk factors.