Previous studies have demonstrated the application of CEST to breast malignancies and its potential to aid tumor characterization. However, artifacts can develop in breast CEST imaging due to strong lipid signals. In this work, CEST-Dixon sequence is used for fat free CEST imaging to characterize suspicious lesions in patients. The CEST effects are higher in the ER- IDC than the ER+ IDC, benign and normal groups. The results also indicate positive correlation of CEST with the Ki-67 level. Thus, CEST-Dixon has a potential for improved non-invasive characterization of breast lesions, potentially differentiating more aggressive from less aggressive tumors.