Successful allogeneic hematopoietic stem cell transplantation for aggressive NK cell leukemia.

Aggressive natural killer cell leukemia (ANKL) is a highly aggressive lymphoproliferative disease. An appropriate therapeutic strategy for ANKL remains to be established, but a few case reports have suggested that allogeneic hematopoietic stem cell transplantation (allo-HCT) can be curative. Here, we report a young woman with ANKL showing central nervous system (CNS) invasion, who has been in complete remission for more than a year after allo-HCT following two courses of intravenous chemotherapy and several rounds of intrathecal chemotherapy. Intensive remission induction chemotherapy followed by conventional myeloablative allo-HCT is a promising approach for long-term remission in cases of this aggressive malignancy.