An improved anti-leukemic effect achieved with donor progenitor cell infusion for relapse patients after allogeneic bone marrow transplantation.

To observe the antileukemic effect in relapse patients by infusion of donor immunocompetent cells with or without granulocyte colony-stimulating factor (G-CSF) mobilization.Twenty patients with leukemia in relapse after allogeneic bone marrow transplantation (allo-BMT) were treated with chemotherapy followed by donor-derived lymphocytes (DDL) without G-CSF mobilization (Group A, n = 11), or donor peripheral blood progenitor cells (PBPCs) with G-CSF mobilization (Group B, n = 9).Five patients in Group A were in hematologic relapse. After DDL infusion, 3 of 5 patients had a temporary complete remission (CR) and relapsed after 3, 7 and 10 months, respectively. One achieved partial remission and died of interstitial pneumonia; and the other one showed no response. Another 6 patients in Group A were in cytogenetic relapse or central nerve system (CNS) leukemia, and all achieved CR and remained in disease free survival (DFS) for 10 to 98 months after DDL infusion. All 9 patients in group B were in hematologic relapse. Three patients with chronic myeloid leukemia (CML) had cytogenetic and molecular remission for 16, 35 and 51 months, respectively after PBPC infusion; and 5 patients with acute lymphoid leukemia (ALL) had CR and were still in CR for 10 to 18 months except 1 patient relapsed soon. And the other one with AML showed no response to the therapy.Donor immunocompetent cells infusion is an effective therapy for relapsed leukemia after allo-BMT, especially for the patients with early (molecular and cytogenetic) or CNS relapse. Infusion of donor PBPC mobilized by G-CSF seems to have more potentiated graft-versus-leukemia (GVL) effect than DDL infusion.