Abstract:Objective To study the clinical features and prognosis of childhood acute myeloid leukemia with myelodysplasia-related changes(AML-MRC).Methods A retrospective analysis was performed on the medical data of 14 children who were diagnosed with AML-MRC from June 2014 to March 2020,including clinical features,laboratory examination results,and prognosis.Results Among the 14 children with AML-MRC,there were 9 boys and 5 girls,with a median age of 11 years(range:1-17 years),a median leukocyte count of 8.3×109/L[range:(2.0-191.0)×109/L],a median hemoglobin level of 73 g/L(range:44-86 g/L),and a median platelet count of 75×109/L[range:(4-213)×109/L]at diagnosis.According to the FAB classification,the children with AML-M5 accounted for 71%(10/14).Among the 14 children,4 had multi-lineage dysplasia(MLD),2 had a history of myelodysplastic syndrome(MDS),5 had MDS-related cytogenetic changes,2 had MLD with MDS-related cytogenetic changes,and 1 had a history of MDS with MLD.The median follow-up time was 10.6 months(range:0.4-54.4 months)for 14 children,among whom 2 gave up treatment immediately after diagnosis and 12 had an evaluable treatment outcome.The 2-year overall survival(OS)rate was 50%±15%,and the 2-year disease-free survival(DFS)rate was 33%±13%.Of the 12 children,7 underwent haploidentical hematopoietic stem cell transplantation(HSCT),among whom 5 achieved DFS and 2 died,with a 2-year OS rate of 71%±17%and a 2-year DFS rate of 43%±19%;5 children underwent chemotherapy alone,among whom 1 achieved DFS,3 died,and 1 was lost to follow-up,with a 2-year OS rate of 40%±30%and a 2-year DFS rate of 30%±24%.There was no significant difference in the survival condition between the transplantation and chemotherapy groups(P>0.05).Conclusions Childhood AML-MRC is often observed in boys,and AML-M5 is the most common type based on FAB classification.Such children tend to have a poor prognosis.HSCT is expected to improve the poor prognosis of children with AML-MRC.However due to the small number of cases,it is necessary to increase the number of cases for further observation.