Second nonmyeloablative allogeneic peripheral blood stem cell transplantation with more immunosuppressive conditioning regimen for the late graft failure of the patient with acute myeloid leukemia

: A 53-year-old woman with acute myeloid leukemia (M2; normal karyotype) in first remission underwent the nonmyeloablative allogeneic peripheral blood stem cell transplantation from her HLA-identical brother, with conditioning consisting of fludarabine and low dose total body irradiation (2Gy). Karyotype analysis of bone marrow on day 28 after the recovery of the hematopoiesis showed 46 XY (20/20). However, pancytopenia progressed from day 130 and the patient became transfusion dependent. Because of the hypoplastic bone marrow and the high ratio (81%) of recipient cells among the peripheral T-cells, she was diagnosed as the late graft failure. Cyclophosphamide was added to the conditioning and the second transplant was performed using the same donor's cryopreserved stem cells. Hematopoiesis recovered and the complete chimerism in T-cells was confirmed on day 28. Although the transplant dose of the CD34 and CD3 positive cells was the same between the two transplantation, the patient suffering from the late graft failure obtained the stable engraftment after the second transplant with more immunosuppressive conditioning regimen.