Abstract: Objective This study was conducted to explore the differential diagnosis of hepatocellular carcinoma (HCC) and hepatic hemangioma (HCH) by contrast-enhanced ultrasonography(CEUS). Methods 75 patients with intrahepatic space-occupying lesions were enrolled in our hospital between January 2020 and December 2021, and all underwent CEUS before liver histopathological diagnosis was made. The receiver operating characteristic (ROC) curves was applied to reveal the diagnostic performance of parameters by CEUS in differentiating HCC from HCH. Results The histopathological examination showed HCH in 35 cases and HCC in 40 cases in our series; the percentages of clear boundary, high echo and uniform internal echo in HCC lesions were 17.5%, 22.5% and 12.5%, all significantly lower than 65.7%, 65.7% and 74.3% (P＜0.05) , while the percentage of grade II blood flow signal was 67.5%, much higher than 14.3%(P＜0.05) in HCH lesions; the CEUS demonstrated that the proportions of high enhancement during arterial stage in HCC lesions was 65.0%, much lower than 91.4% in HCH lesions, while the proportions of low enhancement during portal and delayed stage were 70.0% and 90.0%, both significantly higher than 8.6% and 42.8%(P＜0.05) in HCH foci; the starting time of enhancement, time to peak and enhancement rate in HCC lesions were (9.6±1.8)s,(25.8±4.1)s and (0.5±0.1), all significantly quicker than [(13.2±2.5)s, (32.3±6.7)s and (0.9±0.2), respectively, P＜0.05] in HCH foci; the ROC analysis showed the AUC was 0.935, with the sensitivity of 82.8% and the specificity of 90.0%, when the combination of the starting time of enhancement, time to peak and enhancement rate was applied to predict the differentiation of HCC from HCH, much superior to any parameter done alone (P＜0.05). Conclusion The perfusion and echo changes during CEUS could provide reliable ultrasonic imaging basis for the differential diagnosis of HCH from HCC, and warrants further clinical investigation.

Key words: Hepatoma, Hepatic hemangioma, Contrast-enhanced ultrasound, Blood perfusion, Echo changes, Diagnosis