The presence of additional cytogenetic aberrations in chronic myeloid leukemia cells at the time of diagnosis or their appearance on tyrosine kinase inhibitor therapy predicts the imatinib treatment failure.

the presence of ACA/Ph+ at diagnosis time or their appearance on therapy seems to be clinically relevant not only in terms of the risk of blastic transformation but also in terms of the treatment failure. Gathering patients with various karyotypes and their responses to treatment would allow to set better guidelines and predictions.