Myeloablative unrelated cord blood transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia: comparison with other graft sources from related and unrelated donors.

Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL) is a distinct clinical entity among ALL and is associated with adverse outcomes and higher rates of relapse when conventional chemotherapy is used alone. Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative therapy for patients with Ph+ALL, the impact of graft sources, particularly cord blood transplantation (CBT), on allo-HSCT for patients with Ph+ALL has yet to be clarified. We retrospectively compared clinical outcomes after unrelated CBT (n = 20), unrelated bone marrow transplantation (n = 7), and related bone marrow and peripheral blood stem cell transplantations (n = 13) following myeloablative conditioning in 40 patients with Ph+ALL. Although graft source had no significant impact on survival or relapse, disease status at transplantation did significantly affect outcomes. These data suggest that unrelated CBT is feasible and should be considered early in the course of patients with Ph+ALL when HLA-compatible related and unrelated donors are not available.