Successful treatment of advanced extranodal NK/T cell lymphoma with unrelated cord blood transplantation

Nasal natural killer (NK)/T cell lymphoma is a rare entity of non-Hodgkin's lymphoma which mostly occurs in East Asian countries. The advanced disease above clinical stage III is often refractory to the radiation and chemotherapies, remission is transient even if achieved, and median survival is about 12 months. Thus the prognosis of advanced NK/T cell lymphoma is generally poor, however, the promising results of allogeneic hematopoietic stem cell transplantation for advanced NK/T cell lymphoma have been recently reported. In most of these cases, stem cell sources were human leukocyte antigen (HLA) matched donors and alternative sources were seldom used. We report here a case of a 36-year-old woman who was diagnosed as having an extranodal NK/T cell lymphoma, nasal type. The patient achieved a complete remission after 2 cycles of chemotherapy including Carboplatin, Etoposide, Ifosfamide, and Dexamethasone, but 3-months later relapsed during the search for HLA-matched unrelated donors. She received unrelated cord blood transplantation (CBT) in the second remission achieved by a regimen containing L-asparaginase. The conditioning regimen was 12 Gy of total body irradiation, high-dose cytarabin and cyclophosphamide. FK506 and methotrexate were used for graft-versus-host disease (GVHD) prophylaxis. GVHD involving the intestine and the oral mucosa was observed, but improved without additional immunosuppressive therapies. The patient remains in remission 33 months after CBT. Cord blood thus could be an appropriate stem cell source for patients with advanced NK/T lymphoma who have no HLA matched donors.