Evaluation of the Contrast-Enhanced Ultrasound Nonradiation Treatment Response Assessment LI-RADS v2024 Using Data From a Multi-Center Transarterial Chemoembolization Study

Rationale and Objective

Hepatocellular carcinoma (HCC) locoregional treatment response is commonly evaluated using the Modified Response Evaluation Criteria in Solid Tumors and the American College of Radiology (ACR) Liver Reporting and Data System (LI-RADS) Treatment Response Assessment (TRA) for MRI/CT. This study aims to evaluate the diagnostic performance of the new ACR contrast-enhanced ultrasound (CEUS) Nonradiation TRA LI-RADS v2024 in HCC treated with transarterial chemoembolization (TACE).

Materials and Methods

This retrospective observational study included 87 patients treated with TACE from a previously reported cohort. At 15- and 30-days post-treatment, 68 and 72 HCC lesions were evaluated. Three blinded radiologists with different levels of CEUS experience interpreted the images independently. According to CEUS Nonradiation TRA LI-RADSv2024, both intralesional and perilesional tumor viability were evaluated and final TRA categories were as follows: TR-Nonviable, TR-Equivocal, and TR-Viable. The reference standard used was a composite of histology and imaging.

Results

140 HCC lesions were analyzed. At 15 days post-treatment, the sensitivity (SN), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and accuracy of TR-Viable classification ranged from 72.5–94.3%, 72.2–86.4%, 86.8–91.4%, 65.6–86.7%, 76.9–86.8%, respectively. At 30 days post-treatment, the SN, PPV, and NPV of TR-Viable classification decreased, ranging from 65.9–84.2%, 85.7–90.6%, and 59.5–73.9%, respectively, while the SP increased, ranging from 80.0–88.0%. Kappa values ranged from 0.557–0.730, indicating moderate to substantial agreement.

Conclusion

CEUS Nonradiation TRA LI-RADS is a reliable tool for the detection of viable tumors in lesions treated with TACE and demonstrates reproducibility across readers.