A late-onset Epstein-Barr virus-related lymphoma completely remitted in a child with renal allograft

Lymphomas are frequently encountered malignancies following renal transplantations. A 17-year-old boy was found to have lymphoma 1.5 years after a the first cadaveric transplantation performed due to reflux nephropathy. Polyclonal anti-thymocyte globulin (induction) with prednisolone (PRD), azathioprine (AZT), and tacrolimus (Tac) regimen had been given after the transplantation. A hypoechoic mass (25 mm) was detected in the upper pole of the allograft by renal Doppler ultrasound performed due to graft dysfunction with a high basal serum creatinine (Cr) (2.2 mg/dL). The renal biopsy revealed a large B-cell lymphoma with CD20 staining in the medulla. The serum displayed a positive Epstein-Barr virus (EBV), immunoglobulin (Ig)G, negative IgM with negative DNA-polymerase chain reaction. However, the biopsy was positive for EBV-LMA. The viral status at the time of transplant was unknown. After withdrawing AZT and Tac therapies, a chemoimmunotherapeutic regimen consisting of PRD, cyclophosphamide, and anti-CD20 monoclonal antibody was administered twice. The patient excreted the necrosed tumor particles over a 2-month interval with hydronephrotic colic attacks. The basal Cr improved at 6 months (to 1.4 mg/dL). A low dose of Tac (0.5 mg/d) was added to PRD. The patient has remained in complete remission for 2.5 years with a well-functioning renal allograft. Although this case was a late-onset lymphoma, the patient displayed a picture like excreting stones from the allograft and remitted completely. This case illustrates that localization of a tumor may play a more important role than the elapsed time from transplant in the diagnosis in EBV-related posttransplant lymphoproliferative disease.