Sequential use of chemotherapy and reduced-intensity conditioning (RIC) with 
allogeneic stem cell transplantation (SCT) has been proposed to improve the 
treatment outcomes in patients with high-risk acute myeloid leukemia (AML). 
Here, we present our experience with this procedure in a cohort of 60 AML 
patients with primary induction failure (n = 9); early, refractory, or ≥ second 
relapse (n = 41); or unfavorable cytogenetics (n = 10). A combination of 
fludarabine (30 mg/m²/day), cytarabine (2 g/m²/day), and amsacrine (100 
mg/m²/day) for 4 days was used. After 3 days of rest, RIC was carried out, 
consisting of 4 Gy total body irradiation, antithymocyte globulin 
(ATG-Fresenius), and cyclophosphamide (fludarabine, amsacrine, and cytarabine 
(FLAMSA)-RIC protocol). Prophylactic donor lymphocyte infusions (pDLIs) were 
given in patients with complete remission (CR) and without evidence of 
graft-versus-host disease ≥120 days after SCT. The median time of neutrophil 
engraftment was 17 days. CR was achieved in 47 of 60 patients (78%). Eleven 
patients received pDLIs resulting in long-term CR in eight of them. Non-relapse 
mortality after 1 and 3 years was 25 and 28%, respectively. With a median 
follow-up of 37 months (range, 10-69), 3-year overall survival and 3-year 
progression-free survival were 42 and 33%, respectively. In a multivariate 
analysis, dose of CD34(+) cells >5 × 10⁶/kg (p = 0.005; hazard ratio (HR) = 
0.276), remission of AML before SCT (p = 0.044; HR = 0.421), and achievement of 
complete chimerism after SCT (p = 0.001; HR = 0.205) were significant factors of 
better overall survival. The use of the FLAMSA-RIC protocol in suitable 
high-risk AML patients results in a long-term survival rate of over 40%.