A new adult AML case with an extremely complex karyotype, remission and relapse combined with high hyperdiploidy of a normal chromosome set in secondary AML

Chromosomal abnormalities are diagnostic and prognostic key factors in acute myeloid leukemia (AML) patients, as they play a central role for risk stratification algorithms. High hyperdiploidy (HH), a rare cytogenetic abnormality seen commonly in elder male AML patients, is normally categorized under AML with complex karyotype (CK). Accordingly, patients with HH generally are associated with low remission rates and a short overall survival.

Here we report a case of 21-year-old female, diagnosed with a de novo AML-M1 according to WHO classification and a CK at diagnosis. Cytogenetic, molecular cytogenetic approaches (standard fluorescence in situ hybridization (FISH), array-proven multicolor banding (aMCB)) and high resolution array comparative genomic hybridization (aCGH) analyses revealed a unique complex but still near diploid karyotype involving eleven chromosomes was identified. It included pentasomy 4, three yet unreported chromosomal aberrations t(1;2)(p35;p22), t(1;3)(p36.2;p26.2), and t(10;12)(p15.2;q24.11), and a combination of two cytogenetic events, yet unreported to appear in together, i.e. a reciprocal translocation t(1;3)(p36.2;p26.2) leading to EVI1/PRDM16 gene fusion, and monoallelic loss of tumor suppressor gene TP53. After successful chemotherapeutic treatment the patient experienced a relapse to AML-M1, and she developed secondary AML-M6 with tetraploidy and HH. Unfortunately, the young woman died 8.5 months after initial diagnosis.