[Successful treatment with L-asparaginase-based combination chemotherapy for refractory T-cell post-transplant lymphoproliferative disorder].

A 31-year-old man underwent kidney transplantation in 1996, and had been on immunosuppressants. In 2005, he presented with discomfort on swallowing. Swelling of the left tonsil and a mediastinal mass were observed. A biopsy of the left tonsil showed a monotonous proliferation of atypical lymphocytes suggesting post-transplant lymphoproliferative disorder (PTLD). The reduction of immunosuppressants did not result in any clinical improvements, and he developed bilateral cervical lymphadenopathy. A biopsy of the cervical lymph node also showed monotonous proliferation of TdT, CD3, CD5, CD7, CD10, and CD34-positive immature cells. T-cell receptor rearrangement, but not EBER, was detected. Based on these findings, monomorphic T-cell PTLD was diagnosed. He was treated with four different chemotherapeutic regimens without any clinical improvements, and the PTLD became leukemic. Chemotherapy consisting of L-asparaginase, vincristine, and dexamethasone (LVD) was then given, which resulted in massive tumor lysis. However, after two courses of LVD, complete remission was achieved. T-cell PTLD is a rare disorder, characterized by its refractoriness to chemotherapy as opposed to B-cell PTLD. Our experience suggests that L-asparaginase-based chemotherapy may improve the prognosis of T-cell PTLD.