ARG1 and chronic myelogenous leukemia, BCR-ABL1 positive: Giallongo et al. (13) have previously shown MDSC decrease to normal levels in CML patients following imatinib therapy, and more recently, both imatinib and dasatinib have been shown to modulate the immunosuppressive CML tumor milieu, leading to decreased numbers of MDSC and associated inhibitory molecule arginase-1 expression (121).