Advanced ultrasonography technologies to assess the effects of radiofrequency ablation on hepatocellular carcinoma

Safety margin for CT- and US-guided radiofrequency ablation after TACE of HCC in the hepatic dome

INTRODUCTION

We evaluated the safety margin in patients with hepatocellular carcinoma (HCC) in the hepatic dome who underwent computed tomography (CT)- or ultrasound (US)-guided radiofrequency ablation (RFA).

MATERIAL AND METHODS

Included in this single-center study were 46 patients with 56 HCCs in the hepatic dome undergoing RFA after transarterial chemoembolization from January 2009 to December 2016. Thirty were addressed with CT fluoroscopy and 26 with US guidance. The technical success, safety margin, and local tumor progression (LTP) were evaluated.

RESULTS

Technical success rate was 100% in the CT-RFA and 84.6% in the US-RFA group (p = .04). The average safety margin was 4.8 mm in the CT-RFA and 3.0 mm in the US-RFA group (p = .01). There was no LTP among the HCCs with a safety margin >3 mm achieved in 73.3% CT-RFA and 42.3% US-RFA group tumors (p = .03). Of the US-RFA group, six required additional RFA. There was no significant inter-group difference in LTP (p = .36).

CONCLUSION

CT-guided RFA was superior to US-guided RFA with respect to the technical success rate and the acquisition of an appropriate safety margin in patients with HCC in the hepatic dome.

Intraprocedural contrast-enhanced ultrasound-CT/MR fusion imaging assessment in HCC thermal ablation to reduce local tumor progression: compared with routine contrast-enhanced ultrasound

Purpose: To evaluate whether local tumor progression (LTP) would be further reduced when contrast-enhanced ultrasound (CEUS)-CT/MR fusion imaging was used as intraprocedural assessment method in hepatocellular carcinoma (HCC) thermal ablation compared with routine CEUS. Materials and methods: This prospective non-randomized study was conducted from December 2010 to July 2012. CEUS-CT/MR fusion imaging and routine CEUS were used for treatment response assessment in the ablation procedure of 146 HCCs and 122 HCCs, respectively. Supplementary ablations were performed immediately if necessary. The primary technique efficacy rate, LTP rate and overall survival (OS) rate were calculated. Results: For CEUS-CT/MR fusion imaging and routine CEUS, the technical success rate, technique efficacy rate and supplementary ablation rate were 86.3% (126/146) and 98.4% (120/122) (p = .000), 99.2% (125/126) and 94.2% (113/120) (p = .032), and 14.3% (18/126) and 4.2% (5/120) (p = .006), respectively. The cumulative LTP rate and OS rate were not significantly different between fusion imaging group and routine CEUS group. However, for lesions that were larger than 3 cm or close to major vessels (41 lesions in fusion imaging group and 44 lesions in routine CEUS group, who received transcatheter arterial chemoembolization before ablation), the cumulative LTP rate was significantly lower in fusion imaging group than in routine CEUS group (p = .032). Conclusion: Although intraprocedural CEUS-CT/MR fusion imaging has certain limitations in application, it might provide a potential more efficient method compared with routine CEUS in reducing LTP in HCC thermal ablation, especially for difficult ablation lesions.

Investigating the Accuracy of Ultrasound-Ultrasound Fusion Imaging for Evaluating the Ablation Effect via Special Phantom-Simulated Liver Tumors

The goal of this study was to investigate the accuracy of ultrasound-ultrasound (US-US) fusion imaging for evaluating the ablation effect via phantom-simulated liver tumors. Twenty special phantom models were established, ablated and divided into a complete ablation group (n = 10) and an incomplete ablation group (n = 10). US-US fusion imaging was performed to evaluate the ablation effect. Gross specimens were observed as a standard reference. In this US-US fusion imaging study, the registration success rate was 100% (20/20), and the assessment time was 3.8 ± 0.9 min. The accuracy rate of the evaluation was 100% (20/20). There was no significant difference in the residual pseudo-tumoral area between the evaluation with US-US fusion imaging and gross specimen observation (p = 0.811), and the measurement error was 1.1 ± 0.6 mm. In conclusion, the feasibility and accuracy of US-US fusion imaging when evaluating the ablation effect can be investigated with this phantom-simulated liver tumor ablation model in an ideal state.

Percutaneous ultrasound-guided laser ablation for the treatment of cervical tuberculous lymphadenitis: a pilot study

OBJECTIVE

This study was performed to assess the feasibility, effectiveness, and safety of percutaneous ultrasound (US)-guided laser ablation (LA) for the treatment of cervical tuberculous lymphadenitis (CTBL).

METHODS

We retrospectively reviewed 11 patients with CTBL (mean age, 32.0 ± 8.6 years; range, 18-47 years) who underwent percutaneous US-guided LA from June 2014 to December 2016 with a subsequent 12-month follow-up. We assessed the mean volume reduction and contrast-enhanced US (CEUS) changes of the target lymph nodes as well as the tolerability and adverse effects of LA.

RESULTS

The mean ablation energy was 522 ± 312 J (range, 204-1317 J). All 17 enrolled target lymph nodes were completely non-enhanced after LA treatment as detected by CEUS, indicating complete ablation of all lymph nodes (100%). The target lymph nodes significantly decreased in volume by a mean of 74.0% ± 15.6% from baseline to 12 months after LA. The LA procedure was well tolerated, and none of the 11 patients developed severe complications during the 12-month follow-up.

CONCLUSION

Percutaneous US-guided LA for the treatment of CTBL exhibits good tolerability, minimal invasiveness, and few adverse effects. Further investigations with larger sample sizes and longer follow-up periods are warranted to confirm these findings.

An Image Fusion System for Estimating the Therapeutic Effects of Radiofrequency Ablation on Hepatocellular Carcinoma

Background

During ultrasound-guided radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC), high echoic areas due to RFA-induced microbubbles can help calculate the extent of ablation. However, these areas also decrease visualization of target tumors, making it difficult to assess whether they completely cover the tumors. To estimate the effects of RFA more precisely, we used an image fusion system (IFS).

Patients and methods

We enrolled patients with a single HCC who received RFA with or without the IFS. In the IFS group, we drew a spherical marker along the contour of a target tumor on reference images immediately after administering RFA so that the synchronized spherical marker represented the contour of the target tumor on real-time ultrasound images. When the high echoic area completely covered the marker, we considered the ablation to be complete. We compared outcomes between the IFS and control groups.

Results

We enrolled 25 patients and 20 controls, and the baseline characteristics were similar between the two groups. The complete ablation rates during the first RFA session were significantly higher in the IFS group compared with those in the control group (88.0% vs. 60.0%, P = 0.041). The number of RFA sessions was significantly smaller in the IFS group compared with that in the control group (1.1 ± 0.3 vs. 1.5 ± 0.7, P = 0.016).

Conclusions

The study suggested that the IFS enables a more precise estimation of the effects of RFA on HCC, contributing to enhanced treatment efficacy and minimized patient burden.

Hepatic splenosis mimicking liver metastases in a patient with history of childhood immature teratoma

Background

Hepatic splenosis is rare condition, preceded by splenectomy or spleen trauma, the term refers to nodular implantation of normal splenic tissue in the liver. In patients with history of malignancy in particular, it can be mistaken for metastases and can lead to unnecessary diagnostic procedures or inappropriate treatment.

Case report

Twenty-two-year old male was treated for immature teratoma linked to undescended right testicle after birth. On regular follow-up examinations no signs of disease relapse or long-term consequences were observed. He was presented with incidental finding of mature cystic teratoma after elective surgery for what appeared to be left-sided inguinal hernia. The tumour was most likely a metastasis of childhood teratoma. Origin within remaining left testicle was not found. Upon further imaging diagnostics, several intrahepatic lesions were revealed. Based on radiologic appearance they were suspicious to be metastases. The patient underwent two ultrasound guided fine-needle aspiration biopsies. Cytologic diagnosis was inconclusive. Histology of laparoscopically obtained tissue disclosed presence of normal splenic tissue and led to diagnosis of hepatic splenosis.

Conclusions

Though hepatic splenosis is rare, it needs to be included in differential diagnosis of nodular hepatic lesions. Accurate interpretation of those lesions is crucial for appropriate management of the patient. If diagnosis eludes after cytologic diagnostics alone, laparoscopic excision of nodular lesion is warranted before considering more extensive liver resection.

Combination therapy with sorafenib and radiofrequency ablation for BCLC Stage 0-B1 hepatocellular carcinoma: a multicenter retrospective cohort study

OBJECTIVES

The objective of this study was to evaluate the efficacy of combined therapy using Sorafenib and radiofrequency ablation (RFA) with curative intent for all detectable lesions in patients with Barcelona Clinic Liver Cancer (BCLC) Stage 0-B1 hepatocellular carcinoma (HCC).

METHODS

One hundred and twenty-eight patients with HCC from 12 centers were enrolled in this retrospective study; 64 patients who received Sorafenib plus RFA (Sorafenib-RFA) were compared with a control group treated with RFA alone. The two patient groups were selected with a predefined criterion and matched in terms of their clinical and tumor characteristics at baseline. The primary end point of the study was the incidence of post-RFA HCC recurrence. Secondary end points were overall survival (OS) and treatment toxicity.

RESULTS

During a median follow-up of 134.1 weeks, 49 patients died and 79 survived. The 1-, 2-, and 3-year cumulative incidences of post-RFA recurrence were 40.5%, 62.9%, and 74.5%, respectively, in the Sorafenib-RFA group, and 62.8%, 85.4%, and 92.7%, respectively, in the RFA group. The 1-, 2-, 3-, and 4-year OS rates were 85.6%, 64.0%, 58.7%, and 50.3%, respectively, in the Sorafenib-RFA group, and 80.7%, 47.2%, 30.9%, and 30.9%, respectively, in the RFA group. Thus, the Sorafenib-RFA group exhibited better survival than the RFA alone group.

CONCLUSIONS

Combined therapy with Sorafenib-RFA was associated with a lower incidence of post-RFA recurrence and better OS than RFA alone in patients with BCLC Stage 0-B1 HCC. Although these findings suggest that Sorafenib and RFA is safe and effective for the treatment of early HCC, prospective and randomized controlled trials are needed to validate them.

Real-time image fusion for successful percutaneous radiofrequency ablation of hepatocellular carcinoma

Percutaneous radiofrequency ablation (RFA) is an established nonsurgical curative treatment for hepatocellular carcinoma (HCC). Because of its efficiency and safety, sonography is the most commonly used imaging modality when performing RFA. However, the presence of HCC nodules that are inconspicuous when using conventional sonography is a major drawback of RFA and limits its feasibility as a treatment for HCC. However, a new technology has been developed that synthesizes high-resolution multiplanar reconstruction images using 3-dimensional data and is combined with a position-tracking system using magnetic navigation. With this technology, real-time sonograms can be fused with corresponding computed tomographic, magnetic resonance imaging, or even sonographic volume data; this process is known as real-time image fusion. In this article, we describe this novel imaging method as a useful tool for successful RFA treatment of HCC.

Bipolar radiofrequency ablation for liver tumors: comparison of contrast-enhanced ultrasound with contrast-enhanced MRI/CT in the posttreatment imaging evaluation

OBJECTIVE

The aim of the study was to assess the role of contrast-enhanced ultrasound (CEUS) in treatment response evaluation after percutaneous bipolar radiofrequency ablation (BRFA) for liver tumors.

METHODS

From May 2012 to May 2014, 39 patients with 73 tumors were treated by BRFA. One month after the treatment, CEUS and CEMRI/CECT were conducted to evaluate the treatment response. The results of CEUS were compared with CEMRI/CECT.

RESULTS

Of the 73 tumors ablated, eight (11.0%) were found to have residual viable tumor tissue and 65 (89.0%) were successfully ablated based on CEMRI/CECT within 1-month after ablation. CEUS detected seven of the eight residual tumors and 63 of 65 completely ablated tumors. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CEUS were 87.5% (7/8), 96.9% (63/65), 77.8% (7/9), 98.4% (63/64) and 95.9% (70/73), respectively. The complete ablation (CR) rates for the tumors ≤ 3.0 cm, 3.1-5.0 cm, and >5.0 cm were 96.6% (58/60), 63.6% (7/11), and 0% (0/2), respectively (P<0.001). CR rates were 94.7% (36/38) for primary liver tumors and 82.9% (29/35) for metastatic liver tumors (P=0.212), and were 97.4% (38/39) for the tumors with curative treatment intention and 79.4% (27/34) for those with palliative treatment intention (P=0.037). Major complication was not encountered in this series.

CONCLUSIONS

BRFA is an effective technique of percutaneous ablation for liver tumors and CEUS can be used to assess its therapeutic effect accurately.