Abstract: ObjectiveTo test the capability of intratumoral susceptibility signal intensity (ITSS) in the differentiation of hepatocellular carcinoma (HCC) grades. MethodsRetrospective reviews of 53 patients with pathologically proven HCCs were performed. All patients underwent both conventional MRI and SWI examinations. The morphological score of ITSS and the number of ITSS per square centimeter were calculated, then compared among low-grade and high-grade HCCs. Spearman correlation coefficients were determined between the morphological scores of ITSS, the number of ITSS per square centimeter and HCC grades. Receiver operating characteristic (ROC) curve analysiss was performed to determine the diagnostic accuracy for HCC differentiation. ResultsThe morphological scores of ITSS and the number of ITSS per square centimeter in low-grade HCCs were significantly lower than that in the high-grade HCCs (P<0.05). Spearman correlation coefficient between morphological scores of ITSS and HCC grade was 0.54 (P<0.01), and that between the number of ITSS per square centimeter and HCC grade was 0.38 (P<0.01). In the ROC curve analysis of morphological scores, the AUC was 0.81 (P<0.01) and the optimal sensitivity and specificity were 76%, and 88% respectively with a cut-off of 2. In the ROC curve analysis of the number of ITSS per square centimeter, the area under curve (AUC) was 0.70 (P=0.01) and the optimal sensitivity and specificity were 65%, and 79% respectively with a cut-off of 0.58. ConclusionITSS of SWI had the potential to differentiate HCC grades.