Novel Cytogenetic Aberrations in a Patient of Chronic Myeloid Leukemia with Blast Crisis

Chronic myeloid leukaemia (CML) is a clonal haematological disease which is characterized by a diagnostic karyotypic abnormality t (9;22)(q34;q11) called as Philadelphia (Ph) chromosome. Occurrence of additional chromosomal abnormalities besides the Ph chromosome is defined as clonal evolution (CE) and considered to be a marker of disease progression. A 67-year-old male who was initially evaluated at a private hospital where a diagnosis of acute promyelocytic leukaemia was made on bone marrow aspirate with ambiguous RT-PCR report referred to our centre for further evaluation and treatment. On conventional karyotyping, Ph chromosome along with translocations t(5;13)(q12;p13), t(15;20)(q22;p13) and monosomy 13 was observed in all 20 metaphases. A final diagnosis of CML-myeloid blast crisis with complex cytogenetics was made. Patient succumbed to death within one month of initiation of imatinib therapy.