CHARACTERIZATION OF POSTCARDIAC TRANSPLANT LYMPHOMAS - HISTOLOGY, IMMUNOPHENOTYPING, IMMUNOHISTOCHEMISTRY, AND GENE REARRANGEMENT

Objective.-Between 2% and 9% of cardiac transplant recipients develop posttransplant lymphoproliferative disease, which includes lymphomas. These are usually aggressive Epstein-Barr virus-associated B-cell prol iferations similar to those seen in other immunodeficiency states. A r etrospective pathologic study of the tumor tissue from 21 cardiac tran splant recipients with posttransplant lymphoproliferative disease was undertaken. Design.-Tumor histology, immunohistochemistry, immunopheno typing, and DNA analysis for clonal gene re-arrangement and the presen ce of Epstein-Barr virus DNA were performed. Patients.-The mean patien t age was 53.4 +/- 10.2 years (range 33-67 years); 33% of the patients were alive at the time of study. Results.-HistologicaIly, the samples comprised one Burkitt's lymphoma, three diffuse mixed lymphomas, eigh t diffuse large-cell lymphomas, and nine immunoblastic lymphomas. Thir teen (93%) of 14 samples were infiltrated by small reactive T cells; f ive of the lymphomas qualified as T-cell rich. Of 14 cases studied, 12 had clonal immunoglobulin gene rearrangements, 1 had oligoclonal band s, and 1 exhibited only a germline pattern. The B cells were CD10+, CD 19+, and CD20+, and the reactive T cells were CD2+, CD3+, CD5+, CD7+, CD8f, and CD57+ by immunophenotyping. Conclusions.-ln this patient ser ies, morphologically aggressive lymphomas and disseminated disease occ urred early as well as late after transplantation. Most of the tumors showed a reactive T-cell component, which may represent a host attempt at controlling the B-cell proliferation.