Fludarabine, cytarabine, and G-CSF (FLAG) for the treatment of acute myeloid leukemia relapsing after autologous stem cell transplantation

Twenty-six patients affected by acute myeloid leukemia (AML) who relapsed after autologous stem cell transplantation (ASCT) were treated with the FLAG regimen (fludarabine, cytarabine, and G-CSF). Their median age was 39 years (range 14-59). The median interval from achievement of CR to ASCT was 4 months (2-8). The conditioning regimen was BAVC (BCNU, amsacrine, VP-16, cytarabine) in eight patients, BuCy (busulfan, cyclophosphamide) in 13, and TBI-Cy (total body irradiation, cyclophosphamide) in five. Relapse occurred after a median of 7 months (2-18). ASCT had been performed in CR1 for 23 patients and in CR2 for three. Nineteen patients had been given bone marrow, seven peripheral blood stem cells collected following consolidation plus G-CSF. Overall, CR was obtained by 13 patients (50%), all remitters requiring a single course. The median time for hematological recovery of neutrophils > 500/μl and platelets > 20,000/μl was 24 and 30 days, respectively. The median duration of G-CSF administration was 25 days, while the median hospitalization was 31 days. There were four deaths in induction (15%), while nine patients (35%) were resistant. After achieving CR, two patients received allogeneic BMT, five a second ASCT, and four were consolidated with HD-ARA-C. Only two patients were judged unable to receive any further therapy. There were 14 documented infections, while nine patients experienced fever of unknown origin. WHO > 2 nonhematological toxicity consisted of stomatitis (50%), hepatic dysfunction (11%), diarrhea (11%), and lethargy (4%). Median overall survival and disease-free survival were 6 and 13 months, respectively. Six patients are in CCR at present. We conclude that FLAG is effective in patients with AML who are relapsing after ASCT. The toxicity is acceptable, enabling most patients to receive further treatment, including second transplantation procedures.