ETV6:FLT3 fusion in myeloid/lymphoid neoplasm with eosinophilia

A 45-year-old male presented with no comorbidities, loss of appetite, tiredness, and multiple swellings at cervical, axillary, and inguinal nodal sites.Complete blood count revealed anemia (9.7g/L), leukocytosis (white blood cells-106.510 9/L), thrombocytopenia (Platelet count-11510 9 /L), and neutrophilia (absolute neutrophil count-75.7210 9/L).Lymph node biopsy was consistent with T lymphoblastic leukemia/lymphoma.On imunohistochemistry, the blasts were positive for cluster of differentiation (CD)3, terminal deoxynucleotidyl transferase, and focal LIM domain only 2 and negative for CD20, Myeloperoxidase, CK117, and CD34, expressing molecular immunology borstel 1. Bone marrow morphology revealed hypercellular myeloid preponderant bone marrow with 2% blasts and eosinophilia (10%) [Figure 1a].Immunophenotypic analysis revealed 0.3% abnormal myeloid blasts expressing CD25 and showing overexpression of HL-ADR.In addition, there were 0.17% abnormal T lymphoid blasts which showed moderate expression of CD1a, CD4, CD8, CD7, and CD5.ese blasts were positive for cytoCD3 and negative for CD34 and CD3 [Figure 1b].Chromosomal analysis revealed the karyotype: 46,XY,t(12;13)(p13;q12.2)[19]/46,XY[1] suggestive of ETV6: FLT3 [Figure 1c].Fluorescence in situ hybridization confirmed ETV6 rearrangement.Targeted RNA sequencing tested positive for ETV6:FLT3.e diagnosis was established as myeloid/lymphoid neoplasm with FLT3 rearrangement.e patient was planned for treatment with the modified Berlin-Frankfurt-Mnster 90 protocol and is currently alive with stable disease 12-month post-therapy.is