Hepatocellular carcinoma: therapeutic experience with percutaneous ethanol injection under real-time contrast-enhanced color Doppler sonography with the contrast agent Levovist

Recurrent hepatocellular carcinoma after transcatheter arterial chemoembolization: planning sonography for radio frequency ablation

OBJECTIVES

The purposes of this study were to evaluate the sonographic findings of recurrent hepatocellular carcinoma after transcatheter arterial chemoembolization and to determine how often the lesion conspicuity of the recurrent hepatocellular carcinoma makes it suitable for percutaneous sonographically guided radio frequency ablation.

METHODS

A radiologist prospectively classified the echogenicity of recurrent hepatocellular carcinomas compared to that of the surrounding liver. In addition, the margin of the tumor was classified as follows: grade 1, absolutely indistinguishable; grade 2, less than 50%; grade 3, greater than 50%; and grade 4, clearly demarcated. The lesion conspicuity was also classified as follows: grade 1, absolutely invisible, thus ineligible for percutaneous sonographically guided radio frequency ablation; grade 2, poorly visible, thus unsuitable for ablation; and grade 3, visible and conspicuous, thus suitable for ablation.

RESULTS

A total of 37 consecutive patients (31 men and 6 women; mean age, 59.4 years) with 38 hepatocellular carcinomas were enrolled. The echogenicity of the recurrent hepatocellular carcinomas varied, with the most common finding being a heterogeneous hypoechoic lesion (31.6%), followed by an isoechoic lesion (23.7%), a heterogeneous hyperechoic lesion (18.4%), a homogeneous hypoechoic lesion (13.2%), a lesion with a hypoechoic halo (10.5%), and a homogeneous hyperechoic lesion (2.7%). The margin of the recurrent hepatocellular carcinomas was clearly demarcated in only 28.9% of tumors, whereas 23.7% of the tumors were absolutely indistinguishable from the surrounding liver. The lesion conspicuity was classified as grade 3 in only 60.5% of the recurrent hepatocellular carcinomas.

CONCLUSIONS

The echogenicity and margins of recurrent hepatocellular carcinomas after transcatheter arterial chemoembolization varied. The lesion conspicuity was suitable for sonographically guided radio frequency ablation in only 60.5% of cases.

Sequential changes in echogenicity and conspicuity of small hepatocellular carcinoma on gray scale sonography after transcatheter arterial chemoembolization

OBJECTIVE

The purpose of this study was to assess sequential changes in the echogenicity and conspicuity of small hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE).

METHODS

Seventy patients with nodular HCC underwent 3 serial abdominal sonographic examinations before (t0), immediately after (t1), and 2 to 4 days after (t2) TACE. The echogenicity and conspicuity of the HCC nodules were prospectively graded using a 5-point scale. For all tumors, any changes in the echogenicity and conspicuity scores obtained at t0, t1, and t2 were evaluated. The degree of intratumoral uptake of iodized oil was categorized as compact or noncompact based on unenhanced computed tomographic images. Within each group, the sequential changes in the echogenicity and conspicuity were analyzed. Cross-sectional comparisons of the echogenicity and conspicuity at each time point between the two groups were also made.

RESULTS

Overall, the lesion echogenicity and conspicuity at t1 increased compared with those at t0 (P < .05). Thereafter, both the echogenicity and conspicuity at t2 decreased compared with those at t1 (P < .05). There were 41 HCC nodules with compact iodized oil uptake and 29 with noncompact uptake. Significant sequential changes in the echogenicity (increase at t1 followed by decrease at t2) were noted in both groups, but only the compact group showed a significant change in conspicuity. In a cross-sectional comparison, the compact group showed higher scores for both echogenicity and conspicuity than the noncompact group at both t1 and t2 (P < .05).

CONCLUSIONS

The echogenicity and conspicuity of HCC are increased immediately after TACE. These effects are significantly diminished 2 to 4 days after TACE.

Virtual Sonographic Radiofrequency Ablation of Hepatocellular Carcinoma Visualized on CT but Not on Conventional Sonography

OBJECTIVE

Some nodules cannot be visualized clearly on conventional sonography but can be visualized on CT. In the present study, we evaluated the usefulness of real-time percutaneous ablation therapy under virtual sonographic guidance for these nodules.

SUBJECTS AND METHODS

In vitro experiments were performed with gelatin gel to evaluate the accuracy of virtual sonography. We also studied 50 patients with 58 hepatocellular carcinoma nodules, of whom 18 patients (21 nodules) underwent radiofrequency ablation by virtual sonography. This was the initial treatment for seven of these patients and an additional treatment for 11 patients. Thirty-two patients (37 nodules) received radiofrequency ablation without virtual imaging. The patients receiving standard radiofrequency ablation were retrospectively selected as the historical control group under the same conditions as the study group.

RESULTS

The in vitro gelatin gel study revealed that all punctures had been performed accurately. In both the initial-treatment group and the additional-treatment group, the mean number of treatments with virtual sonography was significantly lower than that without virtual sonography (p = 0.003 for both groups). The rates of local recurrence and complications did not differ significantly between the two groups.

CONCLUSION

In the treatment of nodules not depicted on sonography, radiofrequency ablation assisted by virtual sonography is an efficacious alternative.