A network meta-analysis on the efficacy and prognosis of different interventional therapies for early-stage hepatocellular carcinoma

Loco-regional therapies competing with radiofrequency ablation in potential indications for hepatocellular carcinoma: a network meta-analysis

BACKGROUND/AIMS

There is no clear consensus on the relative ranking of interventional and radiation techniques with indications similar to those of radiofrequency ablation (RFA) for the treatment of early hepatocellular carcinoma (HCC). We used a network meta-analysis to compare the efficacy of non-surgical treatments for early HCC.

METHODS

We searched databases for randomized trials assessing the efficacy of loco-regional treatments for HCCs ≤5 cm with no extrahepatic spread or portal invasion. The primary outcome was the pooled hazard ratio (HR) for overall survival (OS), and secondary outcomes included overall and local progression-free survival (PFS). A frequentist network meta-analysis was performed, and the relative ranking of therapies was assessed with P-scores.

RESULTS

Nineteen studies comparing 11 different strategies in 2,793 patients were included. Chemoembolization plus RFA improved OS better than RFA alone (HR 0.52, 95% confidence interval [CI] 0.33-0.82; P-score=0.951). Cryoablation, microwave ablation, laser ablation, and proton beam therapy had similar effects on OS compared with RFA. For overall PFS, but not local PFS, only chemoembolization plus RFA performed significantly better than RFA (HR 0.61, 95% CI 0.42-0.88; P-score=0.964). Injection of percutaneous ethanol or acetic acid was significantly less effective than RFA for all measured outcomes, while no differences in progression outcomes were identified for other therapies included in the network.

CONCLUSION

Our results suggest that chemoembolization combined with RFA is the best option for local treatment of early HCC. Cases with potential contraindications for RFA may benefit from a tailored approach using thermal or radiation modalities.

Comparative Study of Application of Computed Tomography/Ultrasound and Computed Tomography Imaging Guidance Methods in the Microwave Ablation of Liver Cancer

PURPOSE

The aim of the study is to assess the clinical value of the combined computed tomography (CT)/ultrasound (US) guidance in microwave ablation (MWA) for hepatocellular carcinoma (HCC).

METHODS

From July 16, 2016, to June 20, 2021, medical records of 150 HCC patients treated with MWA were retrospectively analyzed. Ninety-two patients with 115 liver tumors underwent MWA under combined CT/US guidance, and 58 patients with 73 liver tumors received MWA under CT guidance alone. The clinical efficacy of combined CT/US-guided MWA was analyzed. We compared the complications, procedure time, and CT scan times between the 2 groups.

RESULTS

The total complete ablation rate and complete ablation rate of high-risk location tumors were significantly higher in the group treated with combined CT/US guidance ( P = 0.0471 and P = 0.0347, respectively), the imaging guidance modality (odds ratio, 0.303; 95% confidence interval [CI], 0.095-0.970; P = 0.044) was an independent factor for ablation efficacy. These 2 groups also had significant differences in the procedure time ( P = 0.0171), the incidence rate of pneumothorax ( P = 0.0209), abdominal pain ( P = 0.0196), nausea or vomiting ( P = 0.0026), and intraoperative CT scan times ( P < 0.001). The overall complication rates ( P = 0.4023) and recurrence rates ( P = 0.5063) between the 2 groups were not statistically significant. However, CT/US group has a better short-term progressive free survival (log-rank P = 0.103, Breslow P = 0.030). In multivariate analysis, guidance modality (hazard ratio, 0.586; 95% CI, 0.368-0.934; P = 0.025) and Barcelona Clinic Liver Cancer stage (hazard ratio, 2.933; 95% CI, 1.678-5.127; P < 0.001) were risk factor for progressive free survival.

CONCLUSIONS

Percutaneous MWA under the combined CT/US guidance for HCC can improve clinical benefits.

Efficacy and safety of various primary treatment strategies for very early and early hepatocellular carcinoma: a network meta-analysis

BACKGROUND

Several treatments are available for treatment of early and very early-stage Hepatocellular Carcinoma, also known as small Hepatocellular Carcinoma (SHCC). However, there is no consensus with regards to the efficacies of these methods. We aimed at identifying the most effective initial treatment strategy for SHCC through Bayesian network meta-analyses.

METHODS

Studies published between January, 2010, and February, 2021 were searched in EMBASE, Cochrane Library, PubMed and Web of science databases, and conference proceedings for trials. The included studies reported the survival outcomes of very early and early Hepatocellular Carcinoma patients subjected to radiofrequency ablation (RFA), microwave ablation (MWA), surgical resection (SR), transarterial chemoembolization (TACE), percutaneous ethanol injection (PEI), minimally invasive liver surgery (MIS), stereotactic body radiotherapy (SBRT) and cryoablation (CA). Then, data were extracted from studies that met the inclusion criteria. Patient survival data were retrieved from the published Kaplan-Meier curves and pooled. A Bayesian random-effects model was used to combine direct and indirect evidence.

RESULTS

A total of 2058 articles were retrieved and screened, from which 45 studies assessing the efficacies of 8 different treatments in 11,364 patients were selected. The included studies had high methodological quality. Recurrence free survival* (progression/recurrence/relapse/disease/tumor-free survival were combined and redefined as RFS*) and overall survival (OS) outcomes were highest in MIS-treated patients (HR 0·57, 95% confidence intervals [CI] 0·38-0·85; HR 0.48,95% CI 0.36-0.64, respectively), followed by SR-treated patients (HR 0.60, 95% CI 0.50-0.74; HR 0.62, 95% CI 0.55-0.72, respectively). TACE was highly efficacious (58.9%) at decreasing the rates of major complications. Similar findings were obtained through sensitivity analysis, and in most of the prognostic subgroups.

CONCLUSIONS

MIS and SR exhibited the highest clinical efficacies, however, they were associated with higher rates of complications. Ablation is effective in small tumors, whereas SBRT is a relatively promising treatment option for SHCC. More well-designed, large-scale randomized controlled trials should be performed to validate our findings.

The What, the Why, and the How of Liver Ablations: A Practical Guide for the Medical Oncologist

Interventional oncology plays a major role within modern oncological patient management. Image-guided thermal ablation has been recognized as a successful local therapeutic option in patients with primary and secondary malignant liver diseases, as also recalled by the recent European Society of Medical Oncology (ESMO) guidelines on colorectal metastases. As image-guided treatments may be as effective as surgery in selected patients with liver lesions, the clinical oncologist should be familiar with the indications, risks, and technical aspects of liver ablation in order to provide their patients with the best outcomes. This article provides a broad overview of the most commonly used ablation techniques and highlights the most relevant technical aspects such as the ideal setting in the operating theatre; which image-guided methods are available, including the growing application of fusion imaging; or contrast-enhanced ultrasound for guiding/monitoring the procedure. A further aim is to expand the knowledge among medical oncologists about liver ablation procedures and to provide insights into the future perspectives of percutaneous minimally invasive procedures in the liver.

Therapies for hepatocellular carcinoma: overview, clinical indications, and comparative outcome evaluation-part one: curative intention

Hepatocellular carcinoma (HCC) offers unique management challenges as it commonly occurs in the setting of underlying chronic liver disease. The management of HCC is directed primarily by the clinical stage. The most commonly used staging system is the Barcelona-Clinic Liver Cancer system, which considers tumor burden based on imaging, liver function and the patient's performance status. Early-stage HCC can be managed with therapies of curative intent including surgical resection, liver transplantation, and ablative therapies. This manuscript reviews the various treatment options for HCC with a curative intent, such as locablative therapy types, surgical resection, and transplant. Indications, contraindications and outcomes of the various treatment options are reviewed. Multiple concepts relating to liver transplant are discussed including Milan criteria, OPTN policy, MELD exception points, downstaging to transplant and bridging to transplant.

Treatment strategies for early stage hepatocellular carcinoma: a systematic review and network meta-analysis of randomised clinical trials

BACKGROUND

Several treatment strategies for early stage hepatocellular cancers (HCC) have been evaluated in randomised controlled trials (RCTs). This network meta-analysis (NMA) aimed to explore the relative effectiveness of these different approaches on their impact on overall (OS) and recurrence-free survival (RFS).

METHODS

A systematic review was conducted to identify RCT's reported up to 23rd January 2020. Indirect comparisons of all regimens were simultaneously compared using random-effects NMA.

RESULTS

Twenty-eight RCT's, involving 3,618 patients, reporting 13 different treatment strategies for early stage HCC were identified. Median follow-up, reported in 22 studies, ranged from 12-93 months. In this NMA, RFA in combination with iodine-125 was ranked first for both RFS (HR: 0.50, 95% CI: 0.19-1.31) and OS (HR: 0.41, 95% CI: 0.19-0.94). In subgroup with solitary HCC, lack of studies reporting RFS precluded reliable analysis. However, RFA in combination with iodine-125 was associated with markedly better OS (HR: 0.21, 95% CI: 0.05-0.93).

CONCLUSION

This NMA identified RFA in combination with iodine-125 as a treatment delivering better RFS and OS, in patients with early stage HCC, especially for those with solitary HCC. This technique warrants further evaluation in both Asia and Western regions.

Parametric evaluation of impedance curve in radiofrequency ablation: A quantitative description of the asymmetry and dynamic variation of impedance in bovine ex vivo model

Radiofrequency ablation (RFA) is a treatment for liver tumors with advantages over the traditional treatment of surgical resection. This procedure has the shortest recovery time in early stage tumors. The objective of this study is to parameterize the impedance curve of the RFA procedure in an ex vivo model by defining seven parameters (t_1/2, t_minimum, t_end, Z_initial, Z_1/2, Z_minimum and Z_end). Based on these parameters, three performance indices are defined: one to identify the magnitude of impedance curve asymmetry (δ), one Drop ratio (DR) describing the percentage of impedance decrease until the minimum impedance point is reached, and Ascent Ratio (AR) describing the magnitude of increase in impedance from the minimum impedance point to its maximum point. Fifty ablations were performed in a bovine ex vivo model to measure and evaluate the proposed parameters and performance index. The results show that the groups had an average δ of 29.02%, DR of 22.41%, and AR of 545.33% for RFA without the use of saline or deionized solutions. The saline solution and deionized water-cooled groups indicated the correlation of performance indices δ, DR, and AR with the obtained final ablation volume. Therefore, by controlling these parameters and indices, lower recurrence is achieved.

Overall survival and local recurrence following RFA, MWA, and cryoablation of very early and early HCC: a systematic review and Bayesian network meta-analysis

OBJECTIVE

To compare overall survival (OS) and local recurrence (LR) following radiofrequency ablation (RFA), microwave ablation (MWA), and cryoablation (CA) for very early and early hepatocellular carcinoma (HCC).

METHODS

This systematic review was performed according to the PRISMA guidelines. MEDLINE, Embase, and Cochrane databases were searched. Randomized controlled trials (RCTs) and observational studies were included. OS and LR at 1 year and 3 years were assessed. OS was reported as hazard ratio (HR) with 95% credible intervals (CrI) and LR as relative risk (RR) with 95% CrI, to summarize effect of each comparison.

RESULTS

Nineteen studies (3043 patients), including six RCTs and 13 observational studies, met inclusion criteria. For OS at 1 year, as compared to RFA, CA had HR of 0.81 (95% CrI: 0.43-1.51), and MWA had HR of 1.01 (95% CrI: 0.71-1.43). For OS at 3 years, as compared to RFA, CA had HR of 0.90 (95% CrI: 0.48-1.64) and MWA had HR of 1.07 (95% CrI: 0.73-1.50). For LR at 1 year, CA and MWA had RR of 0.75 (95% CrI: 0.45-1.24) and 0.93 (95% CrI: 0.78-1.14), respectively, as compared to RFA. For LR at 3 years, CA and MWA had RR of 0.96 (0.74-1.23) and 0.98 (0.87-1.09), respectively, as compared to RFA. Overall, none of the comparisons was statistically significant. Age of patients and tumor size did not influence treatment effect.

CONCLUSIONS

RFA, MWA, and CA are equally effective for locoregional treatment of very early and early HCC.

KEY POINTS

• There is no significant difference in the OS and LR (at 1 year and 3 years) following ablation of very early and early HCC with RFA, MWA, and CA. • There was no effect of tumor size on the treatment efficacy. • More RCTs comparing CA with RFA and MWA should be performed.

SN, Kulkarni S, Shetty NS, Gupta A, Gupta S. Indian Society of Vascular and Interventional Radiology Expert Consensus Statements for Ablation in Hepatocellular Carcinoma: Part I

Locoregional therapies play an important role in the management of hepatocellular carcinoma (HCC). Percutaneous ablation is one of the most commonly employed nonsurgical methods for treating very early and early HCC. For small HCCs, ablation is potentially curative and competes with surgical resection. The widespread availability and the spectrum of ablative techniques mandate uniform approach among interventional radiologists. Thus, it is desirable to have a consensus regarding various aspects of liver ablation. This article represents a consensus document of the experts from the Indian Society of Vascular and Interventional Radiology involved in the care of patients with HCC. The statements are presented in two parts.

What's New in Percutaneous Ablative Strategies for Hepatocellular Carcinoma and Colorectal Hepatic Metastases? 2020 Update

PURPOSE OF REVIEW

Ablation techniques are now well-established treatment options available for the management of primary and secondary hepatic malignancies. Currently available ablative techniques include radiofrequency ablation (RFA), microwave ablation (MWA), cryoablation, and irreversible electroporation (IRE). Along with advances in navigational devices and targeting technologies, ablation combined with other therapies may be the next therapeutic option in thermal ablation. The purpose of this review is to evaluate the current status of ablative technologies in interventional and medical oncology for management of liver malignancies.

RECENT FINDINGS

With the use of combination techniques (i.e., ablation and transarterial embolization procedures), thermal ablation is now moving toward treating tumors larger than 3 cm in size or tumors with macrovascular invasion. Ongoing trials are examining the optimum timing of combination therapies. Thermal ablation combined with hepatic resection may increase the number of patients with metastatic colorectal carcinoma to the liver who qualify for curative surgery. Combination therapies of thermal ablation and transarterial embolization allow for promising treatment responses for larger HCC. Surgery combined with thermal ablation can potentially increase the number of patients with metastatic colon cancer to the liver who qualify for curative surgery.