BCR and chronic myelogenous leukemia, BCR-ABL1 positive: While the discovery of the Philadelphia chromosome as genetic alteration in CML and the arrival of BCR-ABL targeting TKIs in the clinic have largely replaced the need for IFNα-based treatment in this disease, some recent clinical studies have shown that combination of imatinib and IFNα is superior to either therapy alone, perhaps due to the fact that IFNα targets preferentially CML stem cells (Talpaz et al., 2013).