Chronic myeloid leukaemia in blast phase with t(9;11)(p21;q23), KMT2A::MLLT3 gene fusion

Case: A 51-year-old man presented with lymphadenopathy and increasing fatigue. He had been diagnosed chronic myeloid leukaemia (CML) seven months earlier a suboptimal response to first line nilotinib, failing achieve MR1 BCR-ABL1/ABL persistently >10% (IS). repeat bone marrow examination showed 90% blasts, consistent CML in blast phase (CML-BP). The blasts monoblastic morphology immunophenotype. Conventional karyotype both t(9;22)(q34;q11.2), involving the long arm of chromosome 9, t(9;11)(p21;q23), short same derivative 9. FISH confirmed KMT2A breakapart. core biopsy cervical lymph node demonstrated leukaemic infiltrate BCR-ABL1 mutational analysis did not identify any resistance mutations. Discussion: Progression accelerated or is usually accompanied by series genomic events including mutations, other somatic mutations additional cytogenetic abnormalities (ACAs). Common ACAs include extra Philadelphia chromosome, trisomy 8, 9 isochromosome 17q. rearrangement 11q23 locus are common de novo therapy related acute (both lymphoid), but rarely reported (<1%). few cases show an aggressive clinical presentation, poor outcomes tyrosine kinase inhibitors (TKI).