B-Mode Ultrasonography versus Contrast-Enhanced Ultrasonography for Surveillance of Hepatocellular Carcinoma: A Prospective Multicenter Randomized Controlled Trial.

BACKGROUND: Current practice guidelines recommend the use of ultrasound (US) as an initial surveillance tool for hepatocellular carcinoma (HCC) in patients with liver cirrhosis. Patients with liver cirrhosis, however, frequently have coarse liver parenchyma, masking the presence of tiny nodules during B-mode US. Contrast-enhanced US (CEUS) with Sonazoid has a long-lasting, stable Kupffer phase, which makes it possible to scan the entire liver to depict small lesions. In addition, defect reperfusion imaging (reinjection imaging) enables to determine whether the detected nodule is HCC or not. This prospective, multicenter, randomized, controlled trial was conducted to demonstrate the usefulness of Kupffer phase surveillance in the detection of small HCC compared to B-mode US. METHODS: A total of 23 institutions joined this study. In total, 656 patients with hepatitis B- or C-related liver cirrhosis were randomized either to the B-mode US surveillance group (n = 313) or the Kupffer phase CEUS with Sonazoid surveillance group (n = 309). The primary endpoint was the maximum size of HCC at the time of the first detection. Secondary endpoints included time to HCC detection, number of tumors, and Barcelona Clinic Liver Cancer stage at the first detection, and sensitivity, specificity, and accuracy of each method in the diagnosis, and the cumulative detection rate of HCC. RESULTS: The mean HCC size at the first detection was significantly smaller in the CEUS (13.0 ± 4.1 mm; n = 28) than in the B-mode US group (16.7 ± 4.1 mm; n = 26) (p = 0.011). Of the 38 patients with HCV cirrhosis diagnosed with HCC by US alone, mean tumor size at the first detection was significantly smaller in the 20 patients diagnosed by CEUS alone than in the 18 diagnosed by B-mode US alone (12.7 ± 3.1 vs. 17.6 ± 7.0 mm, p = 0.012). In contrast, among the 16 patients with HBV cirrhosis diagnosed by US alone, mean tumor size at the first detection was similar in the 8 patients diagnosed by CEUS alone and the 8 diagnosed by B-mode US (13.6 ± 6.0 vs. 14.5 ± 2.7 mm, p = 0.715). CONCLUSION: Kupffer phase CEUS surveillance with Sonazoid is extremely useful for the early detection and confirmation of HCC using a reinjection technique. Kupffer phase CEUS with Sonazoid contrast combined with the reinjection technique is, therefore, recommended as first-line screening tool for HCC in patients with liver cirrhosis, especially those with very coarse liver parenchyma.