A Preliminary Report of Allogeneic Stem Cell Transplantation for Patients with Acute Leukemia Conditioned by Triple-alkylating Regimen

Kim, Hee Je; Lee, Jong Wook; Park, Soo Jeong; Suh, Jung Gon; Min, Chang Ki; Eom, Hyeon Seok; Kim, Dong Wook; Min, Woo Sung; Kim, Chun Choo; Kim, Dong Jip

Abstract

BACKGROUND: We assessed the toxicity and feasibility of the three-alkylator combinations as conditioning regimens for allogeneic hemopoietic stem cell transplantation (HSCT) in 23 adult patients with acute leukemia.
METHODS
Sixteen patients were transplanted for acute myeloid leukemia, six for acute lymphoblastic leukemia, and one for myelodysplastic syndrome. Group A included thirteen cases of relapsed refractory, 2 relapsed after first HSCT and group B eight patients in first complete remission or two in second complete remission. Eleven cases received G-CSF mobilized CD34+allogeneic peripheral blood stem cells (PBSCs) in addition to bone marrow (BM) and three in vivo expanded BM by G-CSF and eight unmanipulated BM and one from syngeneic BM after conditioned with busulfan, thiotepa and melphalan (n=14) or cyclophosphamide, thiotepa and melphalan (n=6) or TBI, melphalan and thiotepa (n=3).
RESULTS
Twelve of thirteen patients in group A patients engrafted successfully and only one patient failed to achieve complete remission (CR). All patients in group B had successful engraftment. The median days reaching absolute neutrophil count (ANC) more than 500/microliter and platelet more than 30,000/microliter in group A and group B were 13.4 days (7-22), 17.9 days (9-40) and 16.3 days (10-21), 22.6 days (13-38), respectively. Acute graft vs host disease (GVHD) developed in both groups with the incidence of seven (78%) for group A and six (60%) for group B. The major regimen-related toxicity was mucositis with incidence of 95.7% (22/23). The disease free survival rate after HSCT with median follow-up of 161 days (31-283 days) and 101 days (22-163 days) in each group were 24% and 62.5%, respectively.
CONCLUSION
Although the observation period is limited, this study shows that the combination of triple-alkylating regimens are tolerable as a preparative regimen for allogeneic HSCT for both high-risk and standard-risk leukemic patients. We need to confirm effects of these regimens in prospective randomized-controlled studies in the future. (allo-BMSCT) and 14 cases of autologous peripheral blood stem cell transplantation (aPBSCT) were underwent. With a median follow-up of 293 days (range, 35~510), the relapse rate was 34.1% (14/41 cases) in chemotherapy-only group and 13.5% (5/37 cases) in transplant-group. The probability of disease-free survival (DFS) at 2 years of chemotherapy-only group, aPBSCT group, and allo-BMSCT group were 20.1%, 44.9%, and 90%, respectively. The relapse-probability at 2 years of three groups were 76.1%, 55.1% and 11.1% in order, respectively. Univariate analyses showed that age (P=0.0274) and augmentation with BHAC (p=0.0334) were significant factors for achieving CR.