Anaplastic large cell lymphoma(ALCL)is a rare peripheral T-cell lymphoma. According to anaplastic lymphoma kinase(ALK)expression, the World Health Organization classifies ALCL into two subtypes:ALK-positive or ALK-negative. Anthracycline-based combination chemotherapy is a standard frontline treatment for ALK-positive ALCL, with a long-term event- free survival rate of 60%-70%. For the salvage treatments of relapsed or refractory cases, the efficacies of brentuximab vedotin or ALK inhibitor have been established. We undertook a phase II clinical trial to investigate the efficacy and safety of alectinib, which is a second-generation ALK inhibitor, for relapsed or refractory ALK-positive ALCL. Ten patients were enrolled, and objective responses were documented in eight patients(80%),with six complete responses. Allogeneic hematopoietic stem cell transplantation(allo-HSCT)has also been reported to be one of curative treatments for relapsed or refractory ALCL. However, a high rate of treatment-related mortality was observed in allo-HSCT because of the myeloabrative conditioning regimen. We have reported the efficacy of the reduced-intensity conditioning(RIC)regimen for relapsed or refractory ALCL including the patients who did not obtain complete remission at allo-HSCT. The RIC regimen might be able to improve the outcomes of allo-HSCT by reducing treatment-related mortality.