Abstract: Objective To assess the efficacy of contrast-enhanced ultrasonography in differentiating hepatic space-occupying lesions in high-risk patients with hepatocellular carcinoma. Methods A retrospective analysis was conducted on the imaging data from 160 high-risk patients diagnosed with hepatocellular carcinoma who had presented with space-occupying lesions (204 lesions) between September 2018 and June 2022. All patients underwent contrast-enhanced ultrasonography, with pathological examination being utilized as the gold standard. The consistency between contrast-enhanced ultrasonography finding and pathological results was assessed. Additionally, the arrival time, the peak time, the washout time were compared between benign and malignant liver lesions. Results A total of 204 liver space-occupying lesions were identified in the study cohort, of which 158 malignant lesions (93 hepatocellular carcinoma lesions, 56 metastatic hepatocellular carcinoma, and 9 cholangiocarcinoma) and 46 benign lesions (34 hepatic hemangioma, 7 cirrhotic nodular lesions and 5 hepatic focal nodular hyperplasia lesions). Malignant lesions demonstrated earlier arrival time, shorter peak time, and earlier washout time compared to benign lesions (P<0.05). Among the 204 hepatic focal lesions, contrast-enhanced ultrasound diagnosed 151 malignant lesions and 37 benign lesions, aligning well with the pathological diagnoses and demonstrating good agreement (Kappa=0.772, P<0.05). ROC analysis indicated that the sensitivity, specificity and Youden index of contrast-enhanced ultrasonography in diagnosing malignant liver space-occupying lesions in high-risk patients with hepatocellular carcinoma were 95.57% (151/158), 80.43% (37/46), and 0.760, respectively. Conclusion CEUS emerges as a valuable modality for distinguishing between hepatic space-occupying lesions in high-risk patients with hepatocellular carcinoma.

Key words: Contrast-enhanced ultrasound, Hepatocellular carcinoma, High-risk groups, Liver space-occupying lesions