979PEXPEDIENCE OF MAINTENANCE TREATMENT FOR PATIENTS WITH ACUTE MYELOID LEUKEMIA YOUNGER THAN 65 YEARS ACCORDING TO A RETROSPECTIVE ANALYSIS OF THE EFFICACY OF TWO PROTOCOLS

ABSTRACT Maintenance treatment is a controversial option for patients with acute myeloid leukemia (AML) in complete remission (CR). It is assumed that this approach minimizes residual disease and to prolong the duration of remission. Aims: To examine the efficacy of prolonged maintenance chemotherapy versus intensified consolidation therapy for patients with AML. Methods: A total of 198 patients with median age 43.9 years (range, 15-64) with de novo AML which did not receive allogeneic bone marrow transplantation were enrolled in this report. Of these, 97 patients during 2000-2009 were assigned to receive 2 cycles of induction “3 + 7” (daunorubicin 45 mg/m2 on days 1-3; cytarabine 100 mg/m2 every 12 hours [q12h] on days 1-7) and consolidation of 3 cycles “1 + 5” following by maintenance chemotherapy also cycles for 2 years (trial AML-2000). Other 101 patients during 2007-2012 were treated 2 cycles of induction “3 + 7” or “3 + 7” plus HAM (cytarabine 3 g/m2 per q12h on days 1-3; mitoxantrone 10 mg/m2 on days 3-5) if the complete response (CR) was not documented after the first cycle. Then there were 4 cycles of consolidation HiDAC (3 g/m2 per q12h on days 1-3) without following maintenance (trial AML-2007). Results: In total, 57.1% of patients achieved CR. The 5-year overall survival (OS) rate was 22.3 ± 3.3%, and the disease-free survival (DFS) rate for the 113 patients who achieved CR was 36.3 ± 5.0%. No statistical difference was observed either in the 5-year OS rate (21.5 ± 4.8% vs. 23.1 ± 4.8%; P = 0.5) or in the 5-year DFS rate (39.6 ± 7.3% vs. 49.6 ± 7.3%; P = 0.9) between the two trials. However, the incidence of late recurrence was higher for trial AML-2000 (19.6% vs. 10.9%; P = 0.047). The median length of follow-up of surviving patients was 3.3 and 9.9 years. 5-year OS rate had a negative effect of age ≥ 46 years (P = 0.004), WBC ≥ 50 000/ml (P = 0.035) and the secondary AML (P = 0.020). Intensive consolidation compared with low-intensity concolidation was accompanied by a higher frequency of adverse events III/IV degree, including neutropenia (100% vs. 68.9%; P Conclusions: Maintenance treatment is an effective option for adults with AML that prolongs DFS. Disclosure: All authors have declared no conflicts of interest.