Treatment results of pediatric acute myeloid leukemia with epigenetic drugs addition

Background. Currently, overall survival rate for pediatric patients with acute myeloid leukemia (AML) do not exceed 70 %. The intensity of modern AML chemotherapeutic programs has reached its limit, and further chemotherapy dose escalation for treatment results improvement is impossible, because it fraught with life-threatening complications. It is investigating a new ways of tumor treatment for improvement of AML patient’s survival level: therapeutic efficacy of targeted and epigenetic drugs.Objective: to evaluate the efficacy of epigenetic drugs (azacitidine, decitabine, all-trans-retinoid acid and valproic acid) in combination with AML-BFM 2004 protocol for treatment of pediatric AML.Materials and methods. 80 patients with primary AML diagnosis were enrolled the study. Age was ranged from 8 months to 17 years (median 6.7 ± 0.6 years). From June 2012 to January 2018 all patients were subdivided in two treatment groups. 1st group included 34 patients treated with NII POH AML 2012 protocol, 2nd group – 46 patients treated by AML-BFM 2004 protocol.Results. 3-year relapse-free survival in 1st group, regardless of prognostic risk group, was 66.7 ± 11.7 %, 2nd group – 68.9 ± 9.9 %. Eventfree survival (EFS) for patients from 1st group was 66.7 ± 11.7 %, form 2nd group – 50.4 ± 10.2 %. Overall survival in 1st group was 66.7 ± 14.3 %, 2nd group – 66.9 ± 7.5 %. For patients with unfavorable risk from 1st treatment group 3-year relapse-free survival was 69.1 ± 11.9 %, 2nd – 64.9 ± 11.3 % (p = 0,8). EFS – 69.1 ± 11.9 and 44.8 ± 11.3 % respectively (p = 0,13). 3-year overall survival for patients with unfavorable risk group was 69.4 ± 14.6 and 64.4 ± 7.9 % in 1st and 2nd treatment groups respectively.Conclusion. The efficacy of decitabine in “window” regimen was higher in contrast to azacitidine; epigenetic therapy with AML-BFM 2004 protocol allow us to achieve a higher EFS, because of induction mortality and infection-related death decrease – EFS in 1st group was 16 % higher than in 2nd. Besides, EFS in unfavorable risk group, who treated with epigenetic drugs, was 25 % higher – 69.1 ± 11.9 % and 44.8 ± 11.3 % in 1st and 2nd groups respectively (p = 0.13). Nevertheless, overall survival in both groups was the same – 66 % (1st – 66.7 ± 14.3 % and 2nd – 66.9 ± 7.5 %)