3D fusion is superior to 2D point-to-point contrast-enhanced US to evaluate the ablative margin after RFA for hepatocellular carcinoma

3D-CEUS/MRI-CEUS fusion imaging vs 2D-CEUS after locoregional therapies for hepatocellular carcinoma: a multicenter prospective study of therapeutic response evaluation

OBJECTIVES

To compare the diagnostic accuracy of 3D contrast-enhanced ultrasound (CEUS)/MRI-CEUS fusion imaging with 2D-CEUS in assessing the response of hepatocellular carcinoma (HCC) to locoregional therapies in a multicenter prospective study.

MATERIALS AND METHODS

A consecutive series of patients with HCC scheduled for locoregional treatment were enrolled between April 2021 and March 2023. Patients were randomly divided into 3D-CEUS/MRI-CEUS fusion imaging group (3D/fusion group) or 2D-CEUS group (2D group). CEUS was performed 1 week before and 4-6 weeks after locoregional treatment. Contrast-enhanced MRI (CE-MRI) 4-6 weeks after treatment was set as the reference standard. CEUS images were evaluated for the presence or absence of viable tumors. Diagnostic performance criteria, including sensitivity, specificity, accuracy, and area under the curve (AUC), were determined for each modality.

RESULTS

A total of 140 patients were included, 70 patients in the 2D group (mean age, 60.2 ± 10.4 years) and 70 patients in the 3D/fusion group (mean age, 59.8 ± 10.6 years). The sensitivity of the 3D/fusion group was 100.0% (95% CI: 75.9, 100.0), higher than that of the 2D group (55.6%, 95% CI: 22.7, 84.7; p = 0.019). The specificity of the 3D/fusion group was 96.3% (95% CI: 86.2, 99.4), which was comparable to that of the 2D group (98.4%, 95% CI: 90.0, 99.9; p = 0.915). The AUC of the 3D/fusion group was 0.98 (95% CI: 0.95, 1.00), higher than that of the 2D group (0.77, 95% CI: 0.56, 0.98; p = 0.020).

CONCLUSION

3D-CEUS/MRI-CEUS fusion imaging exhibits superior diagnostic accuracy in evaluating the treatment response to locoregional therapies for HCC.

CLINICAL RELEVANCE STATEMENT

3D-CEUS/MRI-CEUS fusion imaging can be applied for post-treatment assessment of residual tumors in HCC undergoing locoregional treatment, offering potential benefits in terms of accurate diagnosis and clinical management.

KEY POINTS

Evaluating for HCC recurrence following locoregional therapy is important. 3D-CEUS/MRI-CEUS fusion imaging achieved a higher sensitivity than 2D-CEUS in assessing residual tumors after locoregional therapies. 3D-CEUS/MRI-CEUS fusion imaging can help clinicians intervene early in residual HCC lesions after locoregional treatment.

Intelligent automatic registration: is it feasible and efficient for application of ultrasound fusion imaging in liver?

PURPOSE

To evaluate the feasibility and efficiency between the two intelligent auto-registrations (based on hepatic vessels or based on liver surface) and manual registration for US-CT/MR fusion imaging of liver tumours.

METHODS

From May 2017 to December 2017, 30 patients with 30 liver tumours were enrolled in this prospectively study. Two intelligent auto-registrations (based on hepatic vessels or based on liver surface) and manual registration were randomly performed, the registration success rate and efficiency were compared.

RESULTS

In terms of success rate, auto-registrations based on the hepatic vessels (80%) was lower than auto-registration base on liver surface and manual registration (96.67%), but with no statistical difference (P = 0.125). In comparison of the registration efficiency, the efficiency of the auto-registration based on the hepatic vessels was superior to auto-registration based on liver surface and manual registration (P < 0.05). The one-step success rate of auto-registration based on the hepatic vessels (53.33%, 16/30) was higher than that of other two registrations (P < 0.05). Stratified analysis showed that, for the lesion with display of hepatic vessels in grade 3, the success rate of auto-registration based on vessels (0%) was lower than that of auto-registration based on liver surface and manual registration (100%) (P = 0.031).

CONCLUSION

Intelligent auto-registration based on hepatic vessels is a feasible and efficient registration method for US-CT/MR fusion imaging of liver tumours for the patients with clear hepatic vessels. The auto-registration based on liver surface and manual registration can be an effective supplement for cases with poor hepatic vessels display.

Long-term survival analysis of ultrasound-guided percutaneous microwave ablation for hepatocellular carcinoma conforming to the Milan criteria: primary versus recurrent HCC

BACKGROUND

This study compared long-term outcomes between patients with initial hepatocellular carcinoma (IHCC) and those with recurrent HCC (RHCC) treated with microwave ablation (MWA).

METHODS

This retrospective study included 425 patients with HCCs (294 IHCCs and 131 RHCCs) within the Milan criteria who were treated with ultrasound-guided percutaneous MWA between January 2008 and November 2021. All patients with RHCC had previously undergone MWA for initial HCC. Overall survival (OS) and recurrence-free survival (RFS) rates were compared between the IHCC and RHCC groups before and after propensity score matching (PSM).

RESULTS

Before matching, the 1-, 3-, 5-, and 10-year OS rates in the IHCC group were 95.9%, 78.5%, 60.2%, and 42.5%, respectively, which were significantly higher than those in the RHCC group (93.8%, 70.0%, 42.0%, and 6.6%, respectively). This difference remained significant after PSM. However, subgroup analyses suggested that there were no significant differences in OS rates between IHCC and RHCC in patients with solitary HCC ≤3.0 cm, AFP ≤200 ng/mL, ablative margins ≥0.5 cm, or Albumin-Bilirubin (ALBI) grade 1. RFS was significantly higher in IHCC than in RHCC before and after PSM, as well as in subgroup analyses. ALBI grade (hazard ratio (HR), 2.38; 95% CI: 1.46-3.86; p < 0.001), serum AFP level (HR, 2.07; 95% CI: 1.19-3.62; p = 0.010) and ablative margins (HR, 0.18; 95% CI: 0.06-0.59; p = 0.005) were independent prognostic factors for OS of RHCC. Serum AFP(HR, 1.29; 95% CI: 1.02-1.63, p = 0.036) level was the only factor associated with RFS in RHCC.

CONCLUSIONS

MWA yielded comparable OS in IHCC and RHCC patients with solitary HCC ≤3.0 cm, AFP ≤200 ng/mL, ablative margins ≥0.5 cm, or ALBI grade 1.