Usefulness of contrast-enhanced ultrasonography with abdominal virtual ultrasonography in assessing therapeutic response in hepatocellular carcinoma treated with radiofrequency ablation.

OBJECTIVE

Contrast-enhanced computed tomography (CECT) is regarded as the gold standard for assessing the efficacy of radiofrequency ablation (RFA) against hepatocellular carcinoma (HCC). We evaluated the efficacy of virtual ultrasonography (VUS) with contrast-enhanced ultrasonography (CEUS) vs. CECT for assessing the response to RFA.

MATERIALS AND METHODS

Study 1: The therapeutic responses in 22 patients with 26 HCC nodules were assessed by CEUS with VUS as well as by CECT. The efficacy of treatment was based on whether the safety margin was greater than 5 mm after RFA. Study 2: In seven patients with seven HCC nodules, the nodules were treated by RFA and the therapeutic efficacy was assessed by CEUS with VUS. The number of RFA sessions was assessed.

RESULTS

Compared with CECT, CEUS with VUS had a specificity of 77%, a sensitivity of 91.6%, and an accuracy of 84%. When the therapeutic response to RFA was analyzed by CECT only, 1.86 +/- 0.69 assessments (mean) were required, while when response was assessed by CEUS with VUS, 1.14 +/- 0.38 CECT assessments were required (P = 0.03).

CONCLUSION

CEUS with VUS is effective in assessing the therapeutic response to RFA of HCC. Moreover, the number of CECT scans required is reduced by this approach.