To ascertain the clinical implications of high hyperdiploid (HH; 49-65 chromosomes) and triploid/tetraploid (TT; >65 chromosomes) adult acute myeloid leukemia (AML), all such cases were retrieved from the Swedish AML Registry. Of the 3,654 cytogenetically informative cases diagnosed between January 1997 and May 2014, 68 (1.9%) were HH (n = 50)/TT (n = 18). Patients with HH/TT were older than those with intermediate risk (IR) AML (median 71 years vs. 67 years; P = 0.042) and less often had de novo AML (63% vs. 79%; P = 0.004); no such differences were observed between HH/TT and complex karyotype (CK) AML. The overall survival (OS) was similar between patients with HH/TT and CK AML (median 0.9 years vs. 0.6 years; P = 0.082), whereas OS was significantly longer (median 1.6 years; P = 0.028) for IR AML. The OS was shorter for cases with HH than with TT (median 0.6 years vs. 1.4 years; P = 0.032) and for HH/TT AMLs with adverse abnormalities (median 0.8 years vs. 1.1 years; P = 0.044). In conclusion, HH/TT AML is associated with a poor outcome, but chromosome numbers >65 and absence of adverse aberrations seem to translate into a more favorable prognosis. Thus, HH/TT AMLs are clinically heterogeneous and should not automatically be grouped as high risk.
© 2015 Wiley Periodicals, Inc.