Clinical Findings

Histologically, the specimen was made up of a dense, diffuse infiltrate of B-lymphocytes with plasmacytoid differentiation.  There was evidence of high mitotic activity and focal necrosis.  The Immunohistochemistry studies confirmed that the cells were monoclonal for lambda light chain, uniformly positive for CD138, negative for CD20 and CD45 and strongly positive (70% of the infiltrate) for Epstein-Barr virus. The H & E histology and the immunocytochemistry findings are consistent with a post transplant lymphoproliferative disorder, “plasmacytoma-like” type by the WHO classification system.