Epstein-Barr virus-associated T/NK cell-type central nervous system lymphoma which manifested as a post-transplantation lymphoproliferative disorder in a renal transplant recipient.

A 31-year-old male, who had received a cadaveric renal allograft in April 2003, consulted a clinic for a transient hemiplegia in August 2004. At that time, a course observation without medication was chosen. In October 2004, he was admitted to our hospital by ambulance with a clonic seizure and a recurrence of hemiplegia on the right side of his body. Head magnetic resonance imaging (MRI) showed enhanced multifocal nodular lesions with remarkable cerebral edema mainly in the left frontal lobe. A stereotactic brain biopsy was performed, and the pathological diagnosis was nasal type extranodal T/NK cell lymphoma manifested as the post transplant lymphoproliferative disease (PTLD). Systemic staging workups showed no extra-CNS involvement. Because of his renal dysfunction and no sign of any extra-CNS involvement, a reduction of the immunosuppressants and whole brain radiation therapy (WBRT) (40 Gy) without chemotherapy were applied to his therapeutic regimen. After WBRT, MRI showed a remarkable reduction in the number and size of the tumors, and no neurological abnormalities were physically observed. As of December 2006, no sign of recurrence has subsequently been found in both the intra- and extra-CNS.