IFNG and chronic myelogenous leukemia, BCR-ABL1 positive: Although TKIs mainly inhibit the function of these cells in vitro, due to the complexity of the immune system, TKI treatment in vivo upregulates interferon γ (IFNγ) production, especially in the tumor cell microenvironment.6 Accordingly, serum IFNγ levels have been shown to significantly increase during TKI treatment of CML patients in chronic phase.7,8