Epstein-Barr virus-associated high-grade anaplastic plasmacytoma in a renal transplant patient.

Allograft transplant patients have an increased risk of developing polyclonal or monoclonal lymphoproliferative disorders, but high-grade anaplastic plasmacytomas are extremely rare in these patients. We present a renal transplant patient who developed multiple extramedullary high-grade anaplastic plasmacytomas in the oral cavity, the left maxillary antrum, the scalp, the thigh and the upper abdominal wall with no evidence of diffuse bone marrow infiltration. Epstein-Barr virus (EBV) mRNA transcripts were detected within the myeloma cells by in situ hybridization using EBER1-2 probes. Following discontinuation of immunosuppression applied, the patient was treated with a cyclophosphamide-prednisone regimen followed by local irradiation, and a complete remission was achieved within four weeks. We concluded that EBV-associated high-grade anaplastic plasmacytomas constitute one more type of post-transplant lymphoproliferative disorder, and that despite their characterization as highly malignant neoplasms, their clinical behavior is not always aggressive.