¹Division of Hematology, Department of Internal Medicine, Catholic Hemopoietic Stem Cell Transplantation Center, The Catholic University of Korea College of Medicine, Seoul, Korea

Correspondence: Dr W-S Min, The Catholic University of Korea, College of Medicine, St Mary's Hospital, 62, Youido-dong, Youngdungpo-ku, Seoul, 150-713 Korea. E-mail: wsmin@catholic.ac.kr

Received 2 September 2004; Accepted 20 January 2005; Published online 21 March 2005.

Abstract

A total of 11 high-risk Korean acute myeloid leukemia (AML) patients received stem cell transplantation from human leukocyte antigen (HLA) haploidentical donors. Specifically, for eight patients with 2–3 mismatched antigens and bidirectional vectors, we used a newly designed conditioning regimen that consists of total body irradiation, busulfex, ATG, and fludarabine. The median number of CD34+ cells infused was 15.4 10⁶/kg (range, 8–21.2). These patients received neither graft-versus-host disease (GvHD) prophylaxis nor post transplantation G-CSF. All of the patients who were followed up for a median of 6 months (range, 17 days–28 months) showed stable primary engraftment and had no acute GvHD or transplant-related mortality for 100 days post transplant. Three patients with high-risk or refractory disease eventually died in relapse, even with GvH-directed NK alloreactivity. However, the patients in complete remission (CR), with the exception of one patient who is alive at 18 months EFS, died at 4, 6, and 8 months post transplantation due to infections that were associated with delayed immune recovery. Our findings suggest that haploidentical transplantation represents a feasible treatment for patients with high-risk AML in CR, provided that a plan for the enhancement of immune recovery is implemented.