Treatment of Childhood Acute Myeloid Leukemia in Bulgaria

Abstract

Background: During the last four decades the prognosis of childhood acute myeloid leukemia (AML) has been substantially improved due to an increase in complete remission (CR) rates, event-free survival (EFS) and reduced early mortality. The relapsed AML still remains a therapeutic challenge. Aim: To report the AML treatment results of the Bulgarian pediatric oncohematological centers. Materials and methods: Retrospective analysis of the treatment results of children and adolescents (age from 0 to 20 years) with primary AML. Unifi ed AML BFM-backbone type treatment protocol is used. Results: This study included 97 newly diagnosed patients (44 girls and 53 boys) with AML in Bulgaria between 2003 and 2016. The median age at diagnosis was 10.2 years. The most frequent FAB-morphologic subtype was М2 followed by М4. First complete remission (CR1) was achieved in 83 patients (85.6%). The 13-year EFS was 49%, while the overall survival (OS) was 54.6%. Twenty seven (27.8%) patients relapsed, with only 5 of them being still alive towards the end of the study period. Conclusion: The EFS and OS for the children with AML in Bulgaria are comparable with those reported by other European groups. The prognosis of relapsed AML remains still unfavorable for the past 13 years. BACKGROUND

Worldwide trends in population-based survival for children, adolescents, and young adults diagnosed with leukaemia, by subtype, during 2000–14 (CONCORD-3): analysis of individual data from 258 cancer registries in 61 countries

“…The largest increases in 5year survival were seen for lymphoid leukaemia, reaching 90% or higher for children diagnosed during 2010-14 (appendix pp [62][63]. Improvements in 5year survival from acute myeloid leukaemia during 2000-14 were generally much less marked than for lymphoid leukaemia, especially for young adults (aged 20-24 years), reaching 70% by 2010-14 (appendix pp [21][22][23][24][25][26][64][65].…”

“…20 We also detected sizable improvements in 5year survival of 10% or more in Puerto Rico and parts of northern Europe (Estonia, Ireland, Latvia, and Lithuania), eastern Europe (Bulgaria), and Asia (China, Japan, South Korea, Singapore, Taiwan, and Turkey). Such increases can be explained in part by optimisation of treatment protocols (eg, for patients with acute myeloid leukaemia in Bulgaria) 24 or the introduction of financial aid to assist in the costs of treatments for children diagnosed with cancer, such as in South Korea. 25 5year survival from leukaemia in China has increased markedly, from 38% to 52%.…”