Assessment of arterial-phase hyperenhancement and late-phase washout of hepatocellular carcinoma-a meta-analysis of contrast-enhanced ultrasound (CEUS) with SonoVue® and Sonazoid®

Objectives The recognition of arterial phase hyperenhancement (APHE) and washout during the late phase is key for correct diagnosis of hepatocellular carcinoma (HCC) with contrast-enhanced ultrasound (CEUS). This meta-analysis was conducted to compare SonoVue (R)-enhanced and Sonazoid (R)-enhanced ultrasound in the assessment of HCC enhancement and diagnosis.Methods Studies were included in the analysis if they reported data for HCC enhancement in the arterial phase and late phase for SonoVue (R) or in the arterial phase and Kupffer phase (KP) for Sonazoid (R). Forty-two studies (7502 patients) with use of SonoVue (R) and 30 studies (2391 patients) with use of Sonazoid (R) were identified. In a pooled analysis, the comparison between SonoVue (R) and Sonazoid (R) CEUS was performed using chi-square test. An inverse variance weighted random-effect model was used to estimate proportion, sensitivity, and specificity along with 95% confidence interval (CI).Results In the meta-analysis, the proportion of HCC showing APHE with SonoVue (R), 93% (95% CI 91-95%), was significantly higher than the proportion of HCC showing APHE with Sonazoid (R), 77% (71-83%) (p < 0.0001); similarly, the proportion of HCC showing washout at late phase/KP was significantly higher with SonoVue (R), 86% (83-89%), than with Sonazoid (R), 76% (70-82%) (p < 0.0001). The sensitivity and specificity for the detection of APHE plus late-phase/KP washout detection in HCC were also higher with SonoVue (R) than with Sonazoid (R) (sensitivity 80% vs 52%; specificity 80% vs 73% in studies within unselected patient populations).Conclusion APHE and late washout in HCC are more frequently observed with SonoVue (R) than with Sonazoid (R). This may affect the diagnostic performance of CEUS in the diagnosis of HCCs.Clinical relevance statement Meta-analysis data show the presence of key enhancement features for diagnosis of hepatocellular carcinoma is different between ultrasound contrast agents, and arterial hyperenhancement and late washout are more frequently observed at contrast-enhanced ultrasound with SonoVue (R) than with Sonazoid (R).Key Points center dot Dynamic enhancement features are key for imaging-based diagnosis of HCC.center dot Arterial hyperenhancement and late washout are more often observed in HCCs using SonoVue (R)-enhanced US than with Sonazoid (R).center dot The existing evidence for contrast-enhanced US may need to be considered being specific to the individual contrast agent.