Abstract: Objective The aim of this study was to investigate the diagnostic efficacy of contrast-enhanced ultrasound (CEUS) in combination with serum alpha-fetoprotein (AFP), protein induced by vitamin K absence or antagonist-Ⅱ (PIVKA-II) and tumor-specific protein 70 (SP70) levels in patients with intrahepatic space-occupying lesions (SOL). Methods 81 patients with intrahepatic SOL were encountered in our hospital between June 2021 and October 2024, and the diagnosis was proven by histo-pathological examination. At presentation, all patients underwent CEUS to record onset time (OT), initial enhancement intensity (IEI), time to peak (TTP), peak acceleration time (PAT), peak intensity (PI) and echo intensity at 120 seconds (EI-120s). Serum AFP, PIVKA-II and SP70 levels were detected by ELISA. Multivariate Logistic regression analysis was performed to assess risk factors associated with malignant liver tumors, and ROC curve analysis was applied to evaluate diagnostic efficacy. Results Of the 81 patients with intrahepatic SOL, histo-pathological examination proved benign lesions in 35 cases and hepatocellular carcinoma (HCC) in 46 cases; the TIP from CEUS in patients with HCC was (48.4±5.6)s, much shorter than [(56.8±8.1)s, P<0.05], while the PI was (162.5±37.5)dB, much greater than [(124.4±26.4)dB, P<0.05] in those with benign lesions; serum AFP, PIVKA-II and SP70 levels in patients with HCC were (782.9±189.2)ng/mL,(136.3±59.1)mAU/mL and (16.1±6.9)ng/mL, all significantly higher than [(7.9±1.8)ng/mL, (44.6±18.5)mAU/mL and (9.1±4.0)ng/mL, respectively, P<0.05] in those with benign lesions; multivariate Logistic regression analysis showed that PT, TIP, serum AFP, PIVKA-II and SP70 levels were all the independent risk factors for malignant quality (P<0.05); ROC analysis demonstrated that the AUC was 0.980(95%CI:0.948-1.000), with sensitivity of 93.5% and specificity of 97.1%, when the CEUS parameters combined with serum markers in judging the quality of intrahepatic SOL. Conclusion The combination of serum AFP, PIVKA-II and SP70 levels with CEUS has a high diagnostic efficacy in patients with intrahepatic SOL, which might provide a relatively reliable diagnostic tool.

Key words: Hepatoma, Tumor-specific protein 70, Alpha-fetoprotein, Protein induced by vitamin K absence or antagonist-Ⅱ, Contrast-enhanced ultrasound, Diagnosis