Posttransplant lymphoproliferative disorders not associated with Epstein-Barr virus: a distinct entity?

PURPOSEOrgan recipients are at a high risk of posttransplant lymphoproliferative disorders (PTLD) as a result of immunosuppressive therapy. Most B-cell lymphomas are associated with Epstein-Barr virus (EBV) infection. We describe a morphologically and clinically distinct group of PTLD in 11 patients that occurred late after organ transplantation and were not associated with EBV.PATIENTS AND METHODSThere were seven kidney, three heart, and one liver transplant recipients (group I). The clinical manifestations, pathologic findings, treatment, and outcome were compared with those in 21 patients with EBV-associated PTLD treated in our institution (group II). EBV was detected with at least two techniques: Epstein-Barr-encoded RNA (EBER) in situ hybridization with EBER 1 + 2 probes, Southern blotting, and detection of latent membrane protein 1 (LMP1) expression by immunohistochemistry.RESULTSThe time between transplantation and the diagnosis of lymphoma ranged from 180 to 10,220 days in group I (mean, 2,234; me...