Lab Med Online.  2023 Jul;13(3):246-250. 10.47429/lmo.2023.13.3.246.

First Korean Case of Pediatric Acute Megakaryoblastic Leukemia with CBFA2T3::GLIS2 Fusion

• Kim N
• Kim H
• Shin S

• KMID: 2552750
• DOI: http://doi.org/10.47429/lmo.2023.13.3.246

Abstract

Acute megakaryoblastic leukemia (AMKL) is a rare type of acute myeloid leukemia that evolved from primitive megakaryoblasts. We report a case of non-Down syndrome AMKL with CBFA2T3::GLIS2 fusion that has not been described before in Korea. A 20-month-old girl presented with a fever and was diagnosed with AMKL after a bone marrow study and flow cytometry analysis. An RNA fusion test observed a fusion transcript between exons 9 and 2 of the CBFA2T3 and GLIS2 genes, respectively. The patient achieved complete morphological remission after induction chemotherapy. However, her prognosis was poor as measurable residual disease remained, detected using reverse transcription PCR. RNA fusion analysis could be a helpful tool to identify clinically actionable genomic markers for patient risk stratification and measurable residual disease monitoring.

Keyword

Acute megakaryoblastic leukemia; CBFA2T3; GLIS2; Gene rearrangement

Figure

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  Fig. 1 Morphological and genetic analysis. (A) G-banding karyotyping revealed 46,XX,t(5,16)(q22;q23),inc[5]/46,XX[15]. (B) Blasts on a bone marrow aspiration smear (Wright–Giemsa stain, 1,000×). (C) In-house reverse transcription (RT)-PCR using cDNA and (D) subsequent Sanger sequencing confirmed breakpoints in exons 9 and 2 of CBFA2T3 and GLIS2, respectively. (E) Schematic representation of the CBFA2T3::GLIS2 fusion. Abbreviations: NTC, non-template control; NHR, nervy homology regions; MYND, myeloid, nervy, and DEAF-1; ex, exon; TAD, topologically associating domain; TRD, trans-repression domain; ZF, zinc finger.

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  Fig. 2 Flow cytometry findings. Abnormal leukemic cells highlighted in blue (12.28% of total cells) exhibited a CD33+, CD117+, CD41+dim, CD61+dim, and CD34+ phenotype.

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