Efficacy and safety of CT-guided percutaneous thermal ablation for hepatocellular carcinoma adjacent to the second porta hepatis

A Comparison of the Efficacy and Safety of US-, CT-, and MR-Guided Radiofrequency and Microwave Ablation for HCC: A Systematic Review and Network Meta-Analysis

Objectives: The aim of this study was to compare the efficacy and safety of thermal ablation, focusing on radiofrequency ablation (RFA) and microwave ablation (MWA), for hepatocellular carcinoma (HCC) using US-, CT-, and MR-guidance. Methods: PubMed, EMBASE, Cochrane Library, and Web of Science were searched for studies comparing US, CT, and MR guidance in thermal ablation for HCC. Observational studies and randomized controlled trials (RCTs) were included. Overall survival (OS), local tumor recurrence (LTR), primary technique effectiveness (PTE), and major complications were assessed with network meta-analysis. Results: One RCT and 13 retrospective cohort studies reporting on 2349 patients were included. For OS at 3 years, compared to CT, US had hazard ratios (HRs) of 0.98 (95%CI: 0.77-1.26), and MR had HRs of 1.60 (95%CI: 0.51-5.00); For OS at 5 years, US had HRs of 0.80 (95%CI: 0.64-1.01), and MR had HRs of 1.23 (95%CI: 0.52-2.95) compared to CT. LTR rates, PTE, and major complications did not show statistical significance among the three guidance modalities (LTR: RR = 0.29 (95%CI: 0.08-1.14), p = 0.97 MR vs. CT; RR = 0.25 (95%CI: 0.06-1.02), p = 0.97 MR vs. US; PTE: RR = 1.06 (95%CI: 0.96-1.17), p = 0.90 MR vs. CT; RR = 1.08 (95%CI: 0.98-1.20), p = 0.90 MR vs. US. Major complications: RR = 0.27 (95%CI: 0.13-0.59), p = 0.94 MR vs. CT; RR = 0.41 (95%CI: 0.10-1.74), p = 0.94 MR vs. US). Conclusions: CT-, US-, and MR-guided RFA and MWA are equally effective and safe for HCC patients.

Ablative and non-surgical therapies for early and very early hepatocellular carcinoma: a systematic review and network meta-analysis

Background

A wide range of ablative and non-surgical therapies are available for treating small hepatocellular carcinoma in patients with very early or early-stage disease and preserved liver function.

Objective

To review and compare the effectiveness of all current ablative and non-surgical therapies for patients with small hepatocellular carcinoma (≤ 3 cm).

Design

Systematic review and network meta-analysis.

Data sources

Nine databases (March 2021), two trial registries (April 2021) and reference lists of relevant systematic reviews.

Review methods

Eligible studies were randomised controlled trials of ablative and non-surgical therapies, versus any comparator, for small hepatocellular carcinoma. Randomised controlled trials were quality assessed using the Cochrane Risk of Bias 2 tool and mapped. The comparative effectiveness of therapies was assessed using network meta-analysis. A threshold analysis was used to identify which comparisons were sensitive to potential changes in the evidence. Where comparisons based on randomised controlled trial evidence were not robust or no randomised controlled trials were identified, a targeted systematic review of non-randomised, prospective comparative studies provided additional data for repeat network meta-analysis and threshold analysis. The feasibility of undertaking economic modelling was explored. A workshop with patients and clinicians was held to discuss the findings and identify key priorities for future research.

Results

Thirty-seven randomised controlled trials (with over 3700 relevant patients) were included in the review. The majority were conducted in China or Japan and most had a high risk of bias or some risk of bias concerns. The results of the network meta-analysis were uncertain for most comparisons. There was evidence that percutaneous ethanol injection is inferior to radiofrequency ablation for overall survival (hazard ratio 1.45, 95% credible interval 1.16 to 1.82), progression-free survival (hazard ratio 1.36, 95% credible interval 1.11 to 1.67), overall recurrence (relative risk 1.19, 95% credible interval 1.02 to 1.39) and local recurrence (relative risk 1.80, 95% credible interval 1.19 to 2.71). Percutaneous acid injection was also inferior to radiofrequency ablation for progression-free survival (hazard ratio 1.63, 95% credible interval 1.05 to 2.51). Threshold analysis showed that further evidence could plausibly change the result for some comparisons. Fourteen eligible non-randomised studies were identified (n ≥ 2316); twelve had a high risk of bias so were not included in updated network meta-analyses. Additional non-randomised data, made available by a clinical advisor, were also included (n = 303). There remained a high level of uncertainty in treatment rankings after the network meta-analyses were updated. However, the updated analyses suggested that microwave ablation and resection are superior to percutaneous ethanol injection and percutaneous acid injection for some outcomes. Further research on stereotactic ablative radiotherapy was recommended at the workshop, although it is only appropriate for certain patient subgroups, limiting opportunities for adequately powered trials.

Limitations

Many studies were small and of poor quality. No comparative studies were found for some therapies.

Conclusions

The existing evidence base has limitations; the uptake of specific ablative therapies in the United Kingdom appears to be based more on technological advancements and ease of use than strong evidence of clinical effectiveness. However, there is evidence that percutaneous ethanol injection and percutaneous acid injection are inferior to radiofrequency ablation, microwave ablation and resection.

Study registration

PROSPERO CRD42020221357.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment (HTA) programme (NIHR award ref: NIHR131224) and is published in full in Health Technology Assessment; Vol. 27, No. 29. See the NIHR Funding and Awards website for further award information.

Predictive Factors of Treatment Outcomes After Percutaneous Radiofrequency Ablation of Hepatocellular Carcinoma in the Hepatocaval Confluence: A Propensity Score Matching Analysis

RATIONALE AND OBJECTIVES

To compare the efficacy and complications of ultrasound-guided percutaneous radiofrequency ablation of hepatocellular carcinoma (HCC) in the hepatocaval confluence with those of HCC in the non-hepatocaval confluence and to explore the risk factors that lead to radiofrequency ablation failure and patient local tumor progression (LTP).

MATERIALS AND METHODS

From January 2017 to January 2022, 86 patients with HCC in the hepatocaval confluence who had radiofrequency ablation were included. A 1:1 propensity-matched group of patients with HCC in the non-hepatocaval confluence with comparable clinical baseline traits, such as tumor diameter and tumor number, served as the control group. The two groups' complications, primary efficacy rate (PER), technical success rate (TSR), and prognosis were estimated.

RESULTS

After PSM, no significant difference of TSR (91.7% vs 95.8%, p = 0.491) and PER (95.8% vs 97.2%, p = 1.000) and 1-, 3-, and 5-year LTP rate (12.5% vs 9.9%, 28.2% vs 27.7%, 40.8% vs 43.8%, p = 0.959) and 1-, 3-, and 5-year DFS rate (87.5% vs 87.5%, 62.3% vs 54.2%, 18.1% vs 22.6%, p = 0.437) and 1-, 3-, and 5-year OS rate (94.3% vs 95.7%, 72.7% vs 69.6%, 20.9% vs 33.6%, p = 0.904) was detected between the two groups. The tumor-to-IVC distance was an independent risk factor for radiofrequency ablation failure in HCC patients in the hepatocaval confluence (OR = 0.611, p = 0.022). Besides, tumor diameter was an independent risk factor for predicting LTP in patients with HCC in the hepatocaval confluence (HR = 2.209, p = 0.046).

CONCLUSION

HCC in the hepatocaval confluence can be effectively treated with radiofrequency ablation. To maximize treatment efficacy, the tumor-to-IVC distance and tumor diameter should be assessed before the operation begins.

Current perspectives on microwave ablation of liver lesions in difficult locations

Microwave ablation (MWA) is becoming the standard of care in treating liver lesions smaller than 3 cm benefiting from a plethora of radiofrequency ablation (RFA) data in the literature. Some of the advantages of MWA compared to RFA are as follows: Faster ablations, more reproducible and predictable heating, better thermal conductivity in different liver tissue environments, and less susceptibility to heat-sink effect. Despite its many advantages, there are still concerns regarding MWA use in high-risk locations such as near portal veins, near the bile ducts, and near the heart. Some centers have historically considered these tumor locations as a contraindication to percutaneous thermal ablation. In this review, we summarize the current data on the safety of MWA of liver tumors in challenging locations. We also discuss several technical tips with examples provided.

Prediction Model and Nomogram of Early Recurrence of Hepatocellular Carcinoma after Radiofrequency Ablation Based on Logistic Regression Analysis

The purpose of this study was to screen for high-risk factors leading to the early recurrence of hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA) and to construct a prediction model and nomogram. This retrospective study included 108 patients with primary HCC who underwent RFA treatment at the Harbin Medical University Cancer Hospital between January 2018 and June 2019. Four risk factors were screened for using univariate and multivariate logistic regression analyses: number of tumors (hazard ratio [HR] = 14.684, 95% confidence interval [CI]: 1.099-196.215, p = 0.042), neutrophil-to-lymphocyte ratio (NLR) (HR = 2.178, 95% CI: 1.003-4.730, p = 0.049), contrast-enhanced ultrasound (CEUS) performance (HR = 6.482, 95% CI: 1.161-36.184, p = 0.033) and α-fetoprotein (AFP) level (HR = 1.001, 95% CI: 1.000-1.003, p = 0.040). We established a prediction model: Logit(p) = -3.096 + 2.827 × (number of tumors >1 = 1) + 1.851 × (CEUS revealing rapid enhancement of blood flow signal in the arterial phase and clearance in the portal phase = 1) + 1.941 × (NLR >1.55 = 1) + 0.257 × (AFP >32.545 = 1). Through clinical decision curve analysis, the model's threshold was 0.043-0.873, indicating a high clinical value. Patients with a high AFP level, typical CEUS enhancement pattern, multiple tumors and elevated NLR are more likely to relapse early.

Stereotactic radiofrequency ablation of tumors at the hepatic venous confluence

BACKGROUND

Radiofrequency ablation (RFA) is subject to "heat-sink" effects, particularly for treatment of tumors adjacent to major vessels.

METHODS

In this retrospective study, 104 patients with 137 tumors (40 HCC, 10 ICC and 54 metastatic liver tumors) close to (≤1 cm from) the hepatic venous confluence underwent stereotactic RFA (SRFA) between June 2003 and June 2018. Median tumor size was 3.7 cm (1.4-8.5) for HCC, 6.4 cm (0.5-11) for ICC and 3.8 cm (0.5-13) for metastases. Endpoints comprised safety, local tumor control, overall and disease-free survival.

RESULTS

The overall major complication rate was 16.0% (20/125 ablations), where 8 (40%) were successfully treated by the interventional radiologist in the same anesthetic session and did not prolong hospital stay. 134/137 (97.8%) tumors were successfully ablated at initial SRFA. Local recurrence (LR) developed in 19/137 tumors (13.9%). The median and overall survival (OS) rates at 1-, 3-, and 5- years from the date of the first SRFA were 51.5 months, 73.5%, 67.0%, and 49.7% for HCC, 14.6 months, 60.0%, 32.0% and 32.0% for ICC and 38.1 months, 91.4%, 56.5% and 27.9% for metastatic disease, respectively.

CONCLUSION

SRFA represents a viable alternative to hepatic resection for challenging tumors at the hepatic venous confluence.

Robotic laser position versus freehand in CT-guided percutaneous microwave ablation for single hepatocellular carcinoma (diameter < 3 cm): a preliminary study

PURPOSE

To compare the accuracy and safety of robotic laser position (RLP) versus freehand for antenna CT-guided microwave ablation (MWA) of single hepatocellular carcinoma (HCC) (diameter < 3 cm).

MATERIALS AND METHODS

This retrospective study was conducted between May 2020 and June 2021. A total of 40 patients with early HCC who underwent CT-guided MWA were divided into two groups: a freehand group (n = 20) and a RLP group (n = 20). Based on in-plane and out-of-plane data, the actual puncture point error (APPE), number of repositioning procedures, and operative duration were compared using the Mann-Whitney U test. Ablation-related complications were compared using the Chi-squared test.

RESULTS

The mean diameter of HCC patients who received MWA was 2.4 ± 0.5 cm. For in-plane APPE, APPE was comparable between the two groups (p = 0.299). However, for the out-of-plane position, the APPE in the freehand group was higher than that in the RLP group (p = 0.027). The number of repositioning procedures was 0 (range, 0-0) for RLP-guided procedures and 3 (range, 2-5) for freehand procedures, showing a statistically significant difference between the two groups (p < 0.001). The mean operative duration for freehand procedures was 39 min, compared with 26 min for RLP-guided procedures, showing a significant difference (p = 0.013). No deaths or major complications were directly related to MWA. Minor complications in the freehand group were comparable with those in the RLP group (p = 0.313).

CONCLUSION

RLP guidance significantly reduces the number of antenna repositioning procedures in MWA and improves puncture accuracy for target HCC out-of-plane. In addition, the operative duration of robotic guidance was shorter than that of freehand guidance.

Early recurrence after radiofrequency ablation for hepatocellular carcinoma: a multicenter retrospective study on definition, patterns and risk factors

OBJECTIVE

To define an optimal cutoff time to distinguish early and late recurrence in hepatocellular carcinoma (HCC) patients after radiofrequency ablation (RFA), and to determine the risk factors and patterns of early recurrence.

MATERIALS AND METHODS

This retrospective study included HCC patients who developed recurrence after RFA as the primary therapy at three Chinese hospitals from January 2011 to December 2016. The best cutoff time to define early and late recurrence was determined based on differences in post recurrence survival (PRS). The clinical variables were assessed by univariate and multivariate logistic regression analyses.

RESULTS

A total of 279 eligible patients were included. The optimal cutoff time interval after RFA to differentiate early and late recurrence was identified as 12 months (p = 0.029). The independent risk factors of early recurrence were multiple tumors, alpha fetoprotein (AFP) levels, gamma-glutamyl transferase (γ-GT), and serum albumin (ALB) levels. A well-discriminated nomogram was constructed to predict risk of early recurrence. The incidence of intrahepatic distant recurrence (IDR) alone and IDR + extrahepatic recurrence (ER) in early recurrence group was significantly higher than those in late recurrence group (80.73% vs. 66.47%, p = 0.009).

CONCLUSION

Twelve months was determined as the optimal cutoff time for differentiating early and late recurrence after RFA for HCC patients. The factors affecting early recurrence after RFA were multiple tumors, AFP levels, ALB level, and γ-GT level. Patients in early recurrence cohort were more likely to develop IDR alone or IDR + ER.

Effectiveness and safety of irreversible electroporation for recurrent hepatocellular carcinoma ineligible for thermal ablation after surgery

Objectives

To preliminarily evaluate the clinical effectiveness and safety of computed tomography (CT) image-guided irreversible electroporation (IRE) for the treatment of recurrent hepatocellular carcinoma (HCC) after surgical resection.

Methods

From January 2016 to February 2018, 18 patients diagnosed with recurrent HCC after surgical resection received IRE under CT image guidance for 22 tumors. Patients were enrolled for IRE when ineligible for thermal ablation due to tumor location. Clinical records and imaging data were reviewed to assess complete ablation rate, local tumor progression free rate (LTPFR), local tumor progression free survival (LTPFS) and complications after a median follow-up time of 14 months.

Results

Successful complete ablations were achieved in 20/22 (90.1%) tumors. Mean LTPFS was 10.5 ​± ​9.4 months. Overall 3-, 6- and 12-months LTPFR in 22 tumors following IRE were 68.2% (95% confidence interval [CI]: 45%–83%), 59.1% (95% CI: 33%–76%) and 36.4% (95% CI: 17%–56%), respectively. Complications included pneumothorax (2/18, 11.1%), localized pain (3/18, 16.7%), bile duct dilation (1/18, 5.6%) and transient hypertension (1/18, 5.6%). No major complications or treatment-related deaths were observed. The alpha-fetoprotein levels of two patients decreased to the normal range at 3 and 4 months, respectively.

Conclusions

This study showed that percutaneous CT image-guided IRE can serve as a safe and effective treatment for recurrent HCC not suitable for thermal ablation.