We reported an uncommon case of a patient with CML that progressed to BP with the acquisition of core binding factor (CBF) rearrangement, who presented a concomitant MGUS and suffered an early relapse after allo-HSCT due to the acquisition of the ABL1 T315I mutation. Here, CEBPZ is linked to chronic myelogenous leukemia, BCR-ABL1 positive.