2134. Accuracy of Contrast-Enhanced Ultrasound for Hepatocellular Carcinoma (HCC) Post Transcatheter Arterial Chemoembolization (TACE)
Authors * Denotes Presenting Author
  1. William Pryor *; University of North Carolina, School of Medicine
  2. Peter Waybill; Milton S. Hershey Medical Center, Penn State College of Medicine
  3. Nelson Yee; Milton S. Hershey Medical Center, Penn State College of Medicine
  4. Karen Krok; Milton S. Hershey Medical Center, Penn State College of Medicine
  5. Kathryn McGillen; Milton S. Hershey Medical Center, Penn State College of Medicine
Contrast-enhanced ultrasound (CEUS) is comparable to MRI and CT in diagnosing hepatocellular carcinoma (HCC). There are limited studies in the United States evaluating CEUS following transcatheter arterial chemoembolization (TACE) with the only FDA-approved contrast agent Lumason. This prospective trial was performed to evaluate noninferiority between CEUS and the clinical gold standard of CT/MRI using the Liver Reporting & Data System (LIRADS) in evaluating for residual tumor after treatment.

Materials and Methods:
Following institutional review board protocols, adult patients with a first-time diagnosis of HCC were identified and consented for inclusion at the time of TACE. At the time of scheduled follow-up, CT/MR usually performed 2 - 4 months after TACE as directed by the referring clinicians, the patient also received a CEUS with Lumason. Presence or absence of residual tumor, residual/treated tumor size, and portal vein thrombus and assessment of any new liver lesions on CEUS were documented by two separate radiologists. Reports for the CT/MRI were mined for similar data.

There were 26 patients were enrolled (19 male and 7 female) with a mean age of 66.6 years and mean BMI of 30.5. The majority of patients identified as white (84.6%), with the remaining patients identified as black (7.7%) or other (7.7%). Primary cirrhosis etiologies included hepatitis C (n = 14, 53.8%), nonalcoholic fatty liver disease (n = 6, 23.1%), and alcohol-related (n = 5, 19.2%). There were 33 target lesions were identified, size ranging between 0.9-16.8 cm (mean of 3 cm &#177; 2.8); 26 were LIRADS 5 or M. CEUS identified 19 cases of residual tumor (61.3%), 12 cases with no viable disease; while CT/MRI identified 17 cases of residual tumor (51.5%), 16 with no viable disease (48.5%), <em>p</em> = 0.617. Both CEUS and CT/MRI identified 5 portal vein thrombi. 2 lesions were missed or miscategorized on CEUS (6.7%), while 6 were missed or miscategorized on CT/MRI (20%), which was not significantly different (<em>p</em> = 0.289). 6 new lesions were identified on both CEUS and CT/MRI ranging between 0.7-3.3 cm (mean 1.6 cm &#177; 1 cm) on CEUS and 0.7-2.8 cm (mean 1.7 cm &#177; 0.8) on CT/MRI. Of these new lesions, 4 were identified only on CT/MRI and 3 only by CEUS. Post TACE, 11 lesions were echogenic on ultrasound (34.4%), 9 were isoechoic (28.1%), 7 were heterogeneous (21.9%), and 5 were hypoechoic (15.6%). Echogenicities were similar between treated tumors and those with residual disease, except for hyperechoic – 8 incompletely treated tumors were hyperechoic while only 2 treated tumors were hyperechoic.

CEUS is noninferior to CT/MRI in evaluating for residual versus treated tumor in HCC, status post TACE.