[Relationships between Molecular Genetics and Clinical Features of Children with Acute Myeloid Leukemia].

Objective: To analyze the molecular genetic spectrum of children with acute myeloid leukemia (AML), and explore its correlation with clinical characteristics and prognosis.

Methods: The clinical and molecular genetic data of 116 children with newly diagnosed AML in Wuhan Children's Hospital from September 2015 to August 2022 were retrospectively analyzed. The Fisher's exact test was used to analyze the correlation of gene mutations with clinical features, and Kaplan-Meier curve was used to analyze the influences of gene mutations on the prognosis.

Results: NRAS (22%), KRAS (14.9%), and KIT (14.7%) mutations were the most common genetic abnormalities in 116 children with AML. Children with KIT, CEBPA and GATA2 mutations showed a higher median onset-age than those without mutations (all P < 0.05). Children with FLT3-ITD mutation exhibited a higher white blood cell count at initial diagnosis compared to those without mutations (P < 0.05). Children with ASXL2 mutation had lower platelet count and hemoglobin at initial diagnosis than those without mutations (both P < 0.05). KIT mutations were often co-occurred with t(8;21)(q22;q22). There was no significant relationship between gene mutation and minimal residual disease (MRD) remission rate after the first and second induction therapy (P >0.05). KIT and NRAS mutations were not associated with prognosis significantly (P >0.05). The overall survival (OS) rates of children with CEBPA and FLT3-ITD mutations were superior to those without mutations, but the differences were not statistically significant (P >0.05). The 3-year OS rate of 61 children treated by allogeneic hematopoietic stem cell transplantation was 89.8%, which was significantly higher than 55.2% of those only treated by chemotherapy (P < 0.001).

Conclusions: Gene mutations are common in children with AML, and next-generation sequencing can significantly improve the detection rate of gene mutations, which can guide the risk stratification therapy. In addition, FLT3-ITD and KIT mutations may no longer be poor prognostic factors.