Successful outcome with reduced-intensity condition regimen followed by allogeneic hematopoietic stem cell transplantation for relapsed or refractory anaplastic large-cell lymphoma.

We report a retrospective analysis of 38 patients (age ≤ 30 years) who underwent allogeneic hematopoietic stem cell transplantation (allo-SCT) for relapsed or refractory anaplastic large-cell lymphoma (ALCL). Median follow-up for survivors after undergoing allo-SCT was 72 months (range, 35-96 months). Eight patients received reduced-intensity conditioning (RIC) regimens, including three patients with fludarabine plus melphalan-based regimens and five patients with fludarabine plus busulfan-based regimens. The remaining 30 patients received myeloablative conditioning (MAC) regimens. Median ages in the RIC and MAC groups were 24 and 15 years, respectively. The 5-year overall survival rates in the RIC and MAC groups were 100% and 49%, respectively (P = 0.018). The 5-year event-free survival rates in the RIC and MAC groups were 88% and 43%, respectively (P = 0.039). In the RIC group, four of the eight patients showed residual disease at allo-SCT, but all eight patients survived with complete remission (CR), including one patient with relapse. This result suggests that allo-SCT using the RIC regimen may be effective for relapsed or refractory ALCL in children, adolescents, and young adults, even in non-CR cases.