[Cord blood stem cell transplantation for a patient with acute myelogenous leukemia (M1)]

A five-year-old boy with acute myelogenous leukemia in relapse was treated by HLA-matched cord blood stem cell transplantation. The patient was preconditioned with 16 mg/kg of busulfan, 15 mg/kg of thiotepa and 90 mg/kg of cyclophosphamide and 2.45 x 10(7)/kg of cord blood mononuclear cells were infused to the patient on October 19th 1995 without the prophylaxis of graft-versus-host disease (GVHD). From the fifth day following the transplant, rG-CSF was administered at a dose of 300 micrograms/m2/day. Hematopoietic recovery was obtained as following; WBC over 1000/microliters was on +18 day, neutrophil over 500/microliters was on +20 day, reticulocyte over 20/1000 was on +28 day and platelet over 50 x 10(2) microliters was on +91 day. Engraftment was confirmed by DNA restriction fragment length polymorphism (VNTR) on +28 day. In spite of absence of prophylaxis of GVHD, the patient did not develop any signs of GVHD, and leukemia relapsed on +105 day. The patient died of leukemia relapse on +251 day. This is the first case of cord blood stem cell transplantation in Japan.