Molecular Cytogenetic Characterization of a Structural Abnormal Chromosome 16 in a Patient with Acute Myeloid Leukemia Leading to Inversion Chromosome 16 with Concomitant 3'CBFB Deletion.

Acute myeloid leukemia (AML) presents as a heterogeneous blood cancer characterized by the proliferation of immature myeloid cells. We present the case of an 18-year-old female with AML whose symptoms include marked leukocytosis, anemia, as well as thrombocytopenia with spontaneous cerebellar and intracerebral bleeds. The bone marrow biopsy is hypercellular and is expunged by sheets of blast cells with dispersed chromatin, prominent nucleoli, highly irregular nuclei, and moderate cytoplasm. Chromosome analysis reveals an abnormal karyotype with a derivative trisomy 8 and a derivative chromosome 16. The karyotype is described as 47,XX,+der(8)add(8)(q24.3),der(16) inv(16)(p13.1q22)del(16)(q22)[21]/46,XX[1]. DNA FISH analysis reveals abnormalities for RUNX1T1 (8q21.3) and CBFB (16q22) genes. These findings align with that of conventional cytogenetics. The National Comprehensive Cancer Network guidelines for AML state that CBFB gene rearrangements indicate that the patient falls under the favorable risk category. However, AML with core binding factor molecular aberrations is a heterogeneous group and thus the interaction with further cytogenetic abnormalities may result in further pathogenesis. Clinical correlation was suggested.