This study's purpose was to compare DTI heterogeneity index with F18 fluorodeoxyglucose (FDG) standardized uptake value (SUVpeak) in liver metastases and in normal appearing liver tissue. The newly defined diffusion coefficient index (DCV) showed a stronger correlation to SUVpeak (r=0.714, p<0.001) than any other MR metrics evaluated. A threshold of DCV >0.05 and SUVpeak>2.88, correctly classified 28/35 (80%) and 32/35 (91.43%) liver metastases with AUC of 0.939 and 0.989, respectively. DCV, may provide quantitative data of tissue heterogeneity associated with liver metastases. In addition, DCV introduces a potential biomarker index as a quantitative discriminator of liver metastases.