Epstein-Barr virus-associated anaplastic large cell lymphoma in renal transplant patients

A novel association, Epstein-Barr virus-positive Ki-1+/CD30+ anaplastic large cell non-Hodgkin's lymphoma of B-cell phenotype in immunosuppressed renal transplant recipients is reported. Case 1 involved an aggressive clinical evolution, whereas case 2 followed a more "benign" clinical course. Both lymphomas were Epstein-Barr virus-positive as assessed by in situ hybridization, Southern blot, polymerase chain reaction, and immunohistochemical analysis. Both lymphomas contained a single clonal Epstein-Barr virus terminal-repeat fragment. In case 1, clonality was confirmed by the detection of bi-allelic immunoglobulin (Ig) heavy chain gene rearrangement. Case 2 showed germline Ig genes at presentation and oligoclonal Ig heavy chain gene rearrangements at relapse. These results are consistent with the notion that anaplastic large cell lymphoma might arise in a B cell transformed by Epstein-Barr virus at a very early stage, before Ig gene rearrangement. The latter may occur later in the course of clonal evolution, thus permitting investigators to trace intermediate and late stages within a process of multistep lymphomagenesis and/or tumor progression.