Background: The aim was to improve the understanding of an AML1/ETO positive child with acute myeloid leukemia with poor prognosis.
Methods: A case of AML1/ETO positive child with acute myeloid leukemia with poor prognosis was reported. The bone marrow cell morphology, multi-parameter flow cytometry, cytogenetic or molecular genetic test results were analyzed by reviewing relevant literature.
Results: The patient was a young girl with clinical manifestations of respiratory tract infection. Bone marrow smears showed that myeloid primordial cells accounted for 13%, some granulocyte cell bodies are enlarged, visible pathological phenomena such as cytoplasmic vacuoles, binuclear grains, ring rods, and pseudo pelgerhuet malformations were seen (Figure 1). Flow cytometry: abnormal myeloid original cells (12.33%), expression of CD34 and HLA - DR, CD38, CD56, part of the expression of CD117, weak expression of CD13, CD33, MPO, CD19, cCD79a (Figure 2). Chromosome karyotype analysis showed that the chromosome karyotype of peripheral blood was 46, XX, t(8;21)(q22;q22). The quantitative detection result of AML1/ETO fusion gene was 42.15%, and mutations of NRAS, ASXL2, TP53 and TET2 genes were detected by second-generation sequencing. Combined with the above results, AML1/ETO positive with acute myeloid leukemia was diagnosed.
Conclusions: Cytogenetics or molecular genetics is the gold standard for identification of positive AML1/ETO fusion gene. Morphological heterogeneity of AML1/ETO positive AML cells is large, which limits the morphological diagnosis of bone marrow cells to a certain extent, and the comprehensive diagnostic efficiency is significantly better than that of morphology. Leukemia fusion gene AML1/ETO refers to the fusion of AML1 gene located on human chromosome 21q22 and ETO gene 8q22, which is the most common fusion gene in acute myeloid leukemia (AML). This paper reports a case of an AML1/ETO positive child with acute myeloid leukemia with poor prognosis admitted to our hospital and reviews relevant literature.