Accuracy of Contrast-Enhanced Ultrasound for Hepatocellular Carcinoma Post-Transcatheter Arterial Embolization

<b>Background/Objectives</b>: Contrast-enhanced ultrasound (CEUS) is a non-invasive imaging technique with similar accuracy to CT and MRI for the diagnosis of hepatocellular carcinoma (HCC). CEUS offers several advantages in patient populations who have contraindications for CT or MRI. There are limited prospective studies in the United States evaluating the diagnostic equivalence of CEUS following transcatheter arterial chemoembolization (TACE) with same-day CT/MRI. This prospective pilot study compared CEUS and CT/MRI in patients with HCC following TACE in a United States population using Lumason^® contrast agent and the Liver Reporting and Data System (LI-RADS). <b>Methods</b>: Following institutional review board protocols, adult patients with a diagnosis of HCC were included. Follow-up CT/MRI was directed by referring clinicians, and CEUS was performed on the same day. CEUS was used to evaluate for treated lesion(s), new lesion(s), and portal vein thrombus before and after Lumason^®. Any subsequent follow-up imaging was reviewed. <b>Results</b>: In 26 enrolled patients, 33 target lesions were identified (size range 0.9-16.8 cm), and 26 were LI-RADS-5 or -M. CEUS identified 19 cases of residual tumor, 12 with no viable disease; CT/MRI identified 17 cases of residual tumor, 16 with no viable disease (<i>p</i> = 0.617). Both CEUS and CT/MRI identified five portal vein thrombi. Two lesions were missed or miscategorized on CEUS, while six were missed or miscategorized on CT/MRI (<i>p</i> = 0.289). Six new lesions were identified on both CEUS and CT/MRI. Of these new lesions, four were identified only by CT/MRI and three only by CEUS. <b>Conclusions</b>: CEUS is comparable to CT/MRI performed at identical follow-up intervals in evaluating for residual versus treated HCC following first-time TACE.