Large (>or=5.0-cm) HCCs: multipolar RF ablation with three internally cooled bipolar electrodes--initial experience in 26 patients

Combination locoregional and systemic therapies in hepatocellular carcinoma

Locoregional therapies play a fundamental role in the treatment of patients with early and intermediate and locally advanced hepatocellular carcinomas. With encouraging recent advances in immunotherapy-based systemic therapies, locoregional therapies are being both promoted and challenged by new systemic therapy options. Combined locoregional and systemic therapies might enhance treatment outcomes compared with either option alone. This Series paper summarises the existing data on locoregional and systemic therapies for hepatocellular carcinoma, and discusses evidence from studies investigating their combination with a focus on their synergistic efficacy and safety.

Predictors of early and late hepatocellular carcinoma recurrence

Hepatocellular carcinoma (HCC) is the most frequent liver neoplasm, and its incidence rates are constantly increasing. Despite the availability of potentially curative treatments (liver transplantation, surgical resection, thermal ablation), long-term outcomes are affected by a high recurrence rate (up to 70% of cases 5 years after treatment). HCC recurrence within 2 years of treatment is defined as "early" and is generally caused by the occult intrahepatic spread of the primary neoplasm and related to the tumor burden. A recurrence that occurs after 2 years of treatment is defined as "late" and is related to de novo HCC, independent of the primary neoplasm. Early HCC recurrence has a significantly poorer prognosis and outcome than late recurrence. Different pathogenesis corresponds to different predictors of the risk of early or late recurrence. An adequate knowledge of predictive factors and recurrence risk stratification guides the therapeutic strategy and post-treatment surveillance. Patients at high risk of HCC recurrence should be referred to treatments with the lowest recurrence rate and when standardized to combined or adjuvant therapy regimens. This review aimed to expose the recurrence predictors and examine the differences between predictors of early and late recurrence.

Impact of Extended Use of Ablation Techniques in Cirrhotic Patients with Hepatocellular Carcinoma: A Cost-Effectiveness Analysis

BACKGROUND

To evaluate the cost-effectiveness of the extended use of ablation for the treatment of hepatocellular carcinoma (HCC) with cirrhosis in an expert ablation center when compared to the non-extended use of ablation in equivalent tertiary care centers.

METHODS

Consecutive cirrhotic patients with non-metastatic HCC, no prior treatment, and referred to three tertiary care centers between 2012 and 2016 were retrospectively identified. The Bondy group, including all of the patients treated at Jean Verdier Hospital, where the extended use of ablation is routinely performed, was compared to the standard of care (SOC) group, including all of the patients treated at the Beaujon and Mondor Hospitals, using propensity score matching. A cost-effectiveness analysis was carried out from the perspective of French health insurance using a Markov model on a lifetime horizon.

RESULTS

532 patients were matched. The Bondy group led to incremental discounted lifetime effects of 0.8 life-years gained (LYG) (95% confidence interval: 0.4, 1.3) and a decrease in lifetime costs of EUR 7288 (USD 8016) (95% confidence interval: EUR 5730 [USD 6303], EUR 10,620 [USD 11,682]) per patient, compared with the SOC group, resulting in a dominant mean incremental cost-effectiveness ratio (ICER). A compliance with the Barcelona Clinic Liver Classification (BCLC) guidelines for earlier stage contributed to the greater part of the ICER.

CONCLUSION

The extended use of ablation in cirrhotic patients with HCC was more effective and less expensive than the non-extended use of the ablation strategy.

The effectiveness of radiofrequency ablation for patients with BCLC B1 stage hepatocellular carcinoma downgraded by transarterial chemoembolization

PURPOSE

To evaluate the effectiveness of radiofrequency ablation (RFA) as a curative therapy for BCLC B1 stage (beyond Milan criteria but within up-to-seven criteria) hepatocellular carcinoma (HCC) followed by downstageing by using transarterial chemoembolization (TACE).

METHODS

We retrospectively recruited patients underwent RFA alone and who underwent RFA following downstaging into BCLC B1 stage using TACE between April 2011 and August 2017. Overall survival (OS) and recurrence-free survival (RFS) were compared using the Kaplan-Meier method. A propensity score analysis was performed to reduce potential bias.

RESULTS

The downstaging TACE+RFA and RFA alone group comprised 50 and 110 patients, respectively. After propensity score matching, the 1-, 2-, and 3-year OS rates were 100%, 92%, 74%, respectively, the 1-, 2-, and 3-year RFS rates were 40%, 36%, and 20%, respectively, for patients in the downstaging TACE+RFA group. The 1-, 2-, and 3-year OS rates were 96%, 90%, and 82%, respectively, the 1-, 2-, and 3-year RFS rates were 51%, 32%, and 32%, respectively, for patients in the RFA group. No statistical differences were observed between the two groups in terms of OS and RFS before and after matching.

CONCLUSION

RFA after downstaging into BCLC B1 stage using TACE offered a safe and effective treatment regime for patients with HCC beyond the up-to-seven criteria. The intermediate-term OS and RFS of RFA following downstaging into BCLC B1 stage using TACE for HCC were similar to that of patients who were initially in BCLC B1stage.

Comparisons between impedance-based and time-based switching bipolar radiofrequency ablation for the treatment of liver cancer

Switching bipolar radiofrequency ablation (bRFA) is a cancer treatment technique that activates multiple pairs of electrodes alternately based on a predefined criterion. Various criteria can be used to trigger the switch, such as time (ablation duration) and tissue impedance. In a recent study on time-based switching bRFA, it was determined that a shorter switch interval could produce better treatment outcome than when a longer switch interval was used, which reduces tissue charring and roll-off induced cooling. In this study, it was hypothesized that a more efficacious bRFA treatment can be attained by employing impedance-based switching. This is because ablation per pair can be maximized since there will be no interruption to RF energy delivery until roll-off occurs. This was investigated using a two-compartment 3D computational model. Results showed that impedance-based switching bRFA outperformed time-based switching when the switch interval of the latter is 100 s or higher. When compared to the time-based switching with switch interval of 50 s, the impedance-based model is inferior. It remains to be investigated whether the impedance-based protocol is better than the time-based protocol for a switch interval of 50 s due to the inverse relationship between ablation and treatment efficacies. It was suggested that the choice of impedance-based or time-based switching could ultimately be patient-dependent.

Predictors and patterns of recurrence after radiofrequency ablation for hepatocellular carcinoma within up-to-seven criteria: A multicenter retrospective study

PURPOSE

To determine the risk factors and patterns of recurrence after radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) meeting the up-to-seven criteria and to develop a nomogram to predict the recurrence free survival (RFS).

MATERIALS AND METHODS

This retrospective study included 481 HCC patients meeting the up-to-seven criteria and who received RFA as the primary therapy at three Chinese hospitals from January 2013 to December 2016. All clinical variables were assessed by univariate and multivariate Cox regression analyses and a nomogram was constructed to predict the probability of RFS.

RESULTS

The recurrence rate was 50.7 % (244/481). Age > 60 years, male gender, and multiple tumors were independent risk factors of recurrence. The incidence of early and late recurrence was 68.03 % (n = 166) and 31.97 % (n = 78), respectively. Seven patterns of spatial recurrence were identified: local tumor progression (LTP) alone (n = 18, 7.38 %), intrahepatic distant recurrence (IDR) alone (n = 136, 55.74 %), extrahepatic recurrence (ER) alone (n = 21, 8.61 %), IDR + ER (n = 45, 18.44 %), LTP + IDR (n = 16, 6.56 %), LTP + ER (n = 4, 1.64 %) and LTP + IDR + ER (n = 4, 1.64 %). The 1-, 2-, and 3-year RFS rates were 79.63 %, 65.23 %, and 51.03 %, respectively. A well-discriminated and calibrated nomogram was constructed.

CONCLUSIONS

The factors affecting recurrence after RFA were age, gender, and the number of tumors. IDR was the most common type of recurrence after complete ablation.

Hepatocellular carcinoma: French Intergroup Clinical Practice Guidelines for diagnosis, treatment and follow-up (SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, AFEF, SIAD, SFR/FRI)

INTRODUCTION

This document is a summary of the French Intergroup guidelines regarding the management of hepatocellular carcinoma (HCC) published in March 2019.

METHOD

It is a collaborative work under the auspices of most of the French medical societies involved in the management of HCC. It is based on the previous guidelines published in 2017. Recommendations are graded in 3 categories according to the level of evidence of data found in the literature.

RESULTS

The diagnosis and staging of HCC is essentially based on clinical, biological and imaging features. A pathological analysis obtained by a biopsy of tumoral and non-tumoral liver is recommended. HCCs can be divided into 2 groups, taking into account not only the tumor stage, but also liver function. HCCs accessible to curative treatments are tumors that are in Milan criteria or with an AFP score ≤ 2, mainly treated by surgical resection, local ablation or liver transplantation. Intermediate and advanced HCCs with no liver insufficiency, accessible only to palliative treatments, benefit from TACE, SIRT or systemic therapy according to the presence or absence of macrovascular invasion or extrahepatic spread.

CONCLUSION

Such recommendations are in permanent optimization and each individual case must be discussed in a multidisciplinary expert board.

Management of patients with intermediate stage hepatocellular carcinoma

Hepatocellular carcinoma (HCC) causes a significant health burden globally and its impact is expected to increase in the coming years. Intermediate stage HCC, as defined by the Barcelona Clinic Liver Cancer (BCLC) system stage B, represents up to 30% of patients at diagnosis and encompasses a broad spectrum of tumor burden. Several attempts have been made to further subclassify this heterogenous group. The current standard of care recommended by BCLC for intermediate stage HCC patients is transarterial chemoembolization (TACE), with modest outcomes reported. While refinements have been made to TACE technique and patient selection, it remains non-curative. In the real-world setting, only 60% of patients with intermediate stage HCC receive TACE, with the remainder deviating to a range of other therapies that have shown promise in select patient subgroups. These include curative treatments (resection, ablation, and liver transplantation), radiotherapy (stereotactic and radioembolization), systemic therapies, and their combination. In this review, we summarize the classifications and current management for patients with intermediate stage HCC as well as highlight recent key developments in this space.

Phase Contrast Imaging Based Microbubble Monitoring of Radiofrequency Ablation: An ex vivo Study

Background

To explore the potential of synchrotron radiation (SR) phase contrast imaging (PCI) for real-time microbubble formation monitoring during radiofrequency ablation (RFA).

Methods

RFA was performed on ex vivo porcine muscle tissue using unipolar and multi-tined expandable electrodes. Images of microbubble formation in the samples were captured by both SR PCI and absorption contrast imaging. The synchronous ablation temperature was recorded. Each RFA electrode type group contained 6 samples. Ablation size was assessed by histologic examination.

Results

Microbubble formation during RFA could be visualized by SR PCI. The diameter of the microbubbles revealed on the image ranged from tens of microns to several millimeters, and these microbubbles first appeared at the edge of the RFA electrode when the target region temperature reached approximately 60°C and rapidly extended outwards. The average microbubble range measured on PCI was 17.66 ± 0.74 mm. The average range of coagulation necrosis measured by histological examination was 17.22 ± 0.38 mm. There was no significant difference between them (P > 0.05). The range of microbubbles corresponded to the ablation zone.

Conclusion

PCI enabled real-time high-resolution visualization of microbubble formation during RFA, indicating a potential for its use in ablation monitoring.

Radiofrequency Ablation (RFA) Combined with Transcatheter Arterial Chemoembolization (TACE) for Patients with Medium-to-Large Hepatocellular Carcinoma: A Retrospective Analysis of Long-Term Outcome

BACKGROUND The aim of this study was to investigate the prognostic value of radiofrequency ablation (RFA) plus transcatheter arterial chemoembolization (TACE) in hepatocellular carcinoma (HCC) patients with tumor size ranging from 3.0 to 10.0 cm. MATERIAL AND METHODS We retrospectively analyzed data on 201 patients with medium-to-large HCC. According to treatment procedure, the patients were divided into the TACE group (n=124) and the TACE+RFA group (n=77). We recorded data on patient safety, subcapsular hepatic hematoma, large amount of ascites, liver abscess, gallbladder injury, and local skin infection. The overall survival (OS) and progression-free survival (PFS) in the 2 groups were analyzed and compared between groups. RESULTS The median PFS was 4.00 months (3.00-5.00 months) in the TACE group and 9.13 months (6.64-11.62 months) in the TACE+RFA group (P<0.001). Median OS was 12.00 months (8.88-15.13 months) in the TACE group and 27.57 months (20.06-35.08 months) in the TACE+RFA group (P<0.001). In the TACE+RFA group, multivariate Cox regression analysis showed that tumor size ≤5 cm) (HR: 1.952, 95% CI: 1.213-3.143, P=0.006), hepatitis B (HR: 2.323, 95% CI: 1.096-4.923, P=0.028), TACE times (1 or >1) (HR: 1.867, 95% CI: 1.156-3.013, P=0.011), alpha-fetoprotein (AFP) level >200 ng/ml (HR: 2.426, 95% CI: 1.533-3.839, P<0.001), and AST level >40 U/L (HR: 1.946, 95% CI: 1.196-3.166, P=0.007) were independent prognostic factors for overall survival. CONCLUSIONS Combination therapy of TACE with RFA is a safe and effective treatment for patients with medium-to-large HCC, with the long-term beneficial effect of retarding tumor progression and improving PFS and OS.

Iodine-125 Brachytherapy Can Prolong Progression-Free Survival of Patients with Locoregional Recurrence and/or Residual Hepatocellular Carcinoma After Radiofrequency Ablation

Background: Radiofrequency ablation (RFA) for the treatment of hepatocellular carcinoma (HCC) is limited by locoregional recurrence and/or residual tumors caused by incomplete ablation. Iodine-125 brachytherapy can achieve a high local control rate in solid carcinoma, but few studies have assessed the efficacy of this treatment for locoregional recurrence and/or residual HCC after RFA. Objective: To investigate the effectiveness and safety of iodine-125 brachytherapy for treating locoregional recurrence and/or residual HCC in patients treated with RFA. Methods: Eligible study patients were those with locoregional recurrence and/or residual HCC on abdominal imaging performed 1 month after RFA at this institution between February 2009 and September 2014 retrospectively. Patients were divided into either the control group (no treatment until the tumor progressed) or the treatment group (underwent iodine-125 brachytherapy). Progression-free survival (PFS), overall survival (OS), and complications of iodine-125 brachytherapy were evaluated. Results: A total of 42 patients were included in the final analysis, including 29 in the control group and 13 in the treatment group. A total of 457 iodine-125 particles were used (mean 32.8 ± 21.3 mCi per case). The median follow-up time was 25 months. Median PFS was 9 months in the control group and 18 months in the treatment group (p = 0.026). The median OS was 28 months in the control group and 33 months in the treatment group (p = 0.441). There were no major complications observed in patients treated with iodine-125 brachytherapy. Conclusion: Iodine-125 brachytherapy can prolong PFS in patients with locoregional recurrence and/or residual HCC after RFA.

Percutaneous thermal ablation of subcapsular hepatocellular carcinomas: influence of tumor-surface contact and protrusion on therapeutic efficacy and safety

PURPOSE

To evaluate therapeutic efficacy and complication of percutaneous thermal ablation of subcapsular hepatocellular carcinomas (HCCs), and how these may be influenced by the degree of tumor to liver surface contact and tumor protrusion from liver surface.

MATERIALS AND METHODS

Our retrospective study was approved by the Institutional Review Board. Between January 2006 and December 2013, 290 patients (82 women, 208 men; mean age, 64.5 years; range, 33-89 years) with 474 subcapsular (within 1 cm to the liver surface) HCCs (mean size, 23.7 mm; range, 6-71 mm) underwent percutaneous thermal ablation. The HCCs were divided into surface contact group (n = 243) and non-surface contact group (n = 231). The former was further subdivided into exophytic and non-exophytic HCCs. Technical success, primary technique efficacy, local tumor progression (LTP), and secondary technique efficacy rates were analyzed and compared by the chi-square test or Fisher exact test. Prognostic factors for LTP and secondary technique efficacy were assessed using the Cox regression model. Major complications were also assessed.

RESULTS

With median follow-up of 15 months (range, 1-87 months), technical success and primary technique efficacy were 98.7% and 95.7% % in the non-surface contact group; 96.4% and 94.0% in the non-exophytic group; and 100% and 94.7% in the exophytic group (p > 0.05). Tumor size > 3 cm was a significant predictor for LTP, but not for secondary efficacy. Overall major complication rate was 3.8% (24/624) and was not different among the three groups.

CONCLUSION

Subcapsular HCCs can be effectively treated with thermal ablation techniques. Degree of tumor-surface contact including moderate protrusion does not appear to limit feasibility or procedure effectiveness.

KEY POINTS

• Subcapsular HCCs can be effectively treated with thermal therapy when proper image-guided technique and assistive techniques are applied. • Degree of tumor surface contact including moderate protrusion does not appear to limit feasibility or procedure effectiveness. • Major complications after percutaneous thermal ablation of subcapsular HCCs such as tumor seeding can be minimized by avoiding breach of the tumor capsule exposed to the peritoneal surface and use of tract ablation.

No-Touch Multi-bipolar Radiofrequency Ablation for the Treatment of Subcapsular Hepatocellular Carcinoma ≤ 5 cm Not Puncturable via the Non-tumorous Liver Parenchyma

PURPOSE

The percutaneous ablation of subcapsular hepatocellular carcinoma (S-HCC) may involve a risk of complications such as hemorrhage and tumor seeding, mainly linked to the direct tumor puncture often inevitable with mono-applicator ablation devices. The purpose of this study was to assess the efficacy and safety of no-touch multi-bipolar radiofrequency ablation (NTMBP-RFA) for the treatment of S-HCC ≤ 5 cm not puncturable via the non-tumorous liver parenchyma.

MATERIALS AND METHODS

Between September 2007 and December 2014, 58 consecutive patients (median age: 63 years [46-86], nine females) with 59 S-HCC ≤ 5 cm (median diameter: 25 mm [10-50 mm]), not puncturable via the non-tumorous liver parenchyma, were treated with NTMBP-RFA. Response and follow-up were assessed by CT or MRI. Complications were graded using the Cardiovascular and Interventional Radiological Society of Europe classification. Overall local tumor progression (OLTP)-free survival was assessed using the Kaplan-Meier method. A Cox proportional model evaluated the factors associated with OLTP. Signs of peritoneal or parietal tumor seeding were noted during follow-up imaging studies.

RESULTS

A complete ablation was achieved in 57/58 patients (98.3%) after one (n = 51) or two (n = 6) procedures. Three patients (5.2%) experienced complications (sepsis, cirrhosis decompensation; CIRSE grade 2 or 3). After a median follow-up period of 30.5 months [1-97], no patients had tumor seeding. The 1, 2 and 3-year OLTP-free survival rates were 98%, 94% and 91%, respectively. No factors were associated with OLTP.

CONCLUSION

NTMBP-RFA is a safe and effective treatment for S-HCC not puncturable via the non-tumorous liver parenchyma.

Multibipolar Radiofrequency Ablation for the Treatment of Mass-Forming and Infiltrative Hepatocellular Carcinomas > 5 cm: Long-Term Results

AIMS AND BACKGROUND

Only few patients with cirrhosis and hepatocellular carcinoma (HCC) larger than 5 cm are amenable to resection or straight liver transplantation, and in such circumstances, multibipolar radiofrequency ablation (mbp-RFA) could be a reliable alternative. This study was aimed to assess the long-term outcome in patients treated with mbp-RFA for unresectable HCC > 5 cm.

METHODS

Eighty-three consecutive patients with cirrhosis (median age 70 years [37-93 years], 67 males, BCLC A/B/C: 54/21/8, 74 naive) with up to three HCCs, the largest > 5 cm in diameter (median: 6.2 cm, 5.1-9 cm, 22 infiltrative forms, 12 with segmental portal invasion of which 10 were infiltrative forms) were treated with mbp-RFA. Overall (OS) and recurrence-free (RFS) survival and their associated predictive factors were assessed.

RESULTS

Complete ablation was observed in 78/83 (94%) patients. Thirty-one side effects occurred, including 6 (7%) severe complications. After a median follow-up of 26.1 months (1-112 months), in naive patients the 3- and 5-year OS was 51% (38-62) and 24% (13-36), 63 and 30% for mass-forming and 25 and 6% for infiltrative form, respectively. Infiltrative form (HR: 2.5 [1.33-4.69], p = 0.004) was the only independent OS predictor. In naive patients with mass-forming and infiltrative form, the 3- and 5-year RFS were 47 and 17 and 18 and 18%, respectively. Alpha-fetoprotein (HR: 2.86 [1.32-6.21], p = 0.008), multinodular form (HR: 2.74 [1.4-5.38], p = 0.003) and infiltrative form (HR: 3.43 [1.67-7.01], p = 0.0007) were independent RFS predictors.

CONCLUSIONS

mbp-RFA offers good OS in inoperable patients with cirrhosis and large HCC, with acceptable safety profile. For infiltrative forms, although mbp-RFA leads to complete responses in more than 80% cases, few only remain tumor progression-free in long-term.

Radiofrequency ablation following artificial ascites and pleural effusion creation may improve outcomes for hepatocellular carcinoma in high-risk locations

PURPOSE

To investigate the outcomes of radiofrequency ablation (RFA) following artificial ascites (AA) and artificial pleural effusion (AP) creation for hepatocellular carcinoma (HCC) in high-risk locations.

MATERIALS AND METHODS

Eligible patients were divided into 2 study periods (non-AAAP and AAAP groups) with AAAP performed in the latter period. Local tumor progression, primary technique effectiveness and complications were compared between patients with and without AAAP. Cumulative probability of local tumor progression and overall survival were estimated with Kaplan-Meier curves.

RESULTS

One hundred thirty-eight patients with 195 tumors were evaluated. AAAP was performed in 48 patients with 76 tumors. Local tumor progression rates at 12 and 24 months were 9.3% and 22.2% in the non-AAAP group versus 5.5% and 9% in the AAAP group (p < 0.0001). Primary technique effectiveness was achieved in 76.5% of the non-AAAP group versus 89.5% of the AAAP group (p = 0.046). Night (7.6%) major complications occurred in the non-AAAP group and 2 (2.6%) cases occurred in the AAAP group. Therapy-oriented severity grading system after RFA was lower in the AAAP group (p = 0.02). Overall survival rates at 12 and 24 months were 85.6% and 77.7% in the non-AAAP group versus 97.2% and 89.7% in the AAAP group (p = 0.033).

CONCLUSION

RFA following AA and AP for high-risk located HCC may improve outcomes.

Periostin involved in the activated hepatic stellate cells-induced progression of residual hepatocellular carcinoma after sublethal heat treatment: its role and potential for therapeutic inhibition

BACKGROUND

Incomplete thermal ablation may induce invasiveness of hepatocellular carcinoma (HCC). Here, we investigated whether activated hepatic stellate cells (HSCs) would accelerate the progression of residual HCC after sublethal heat treatment, and thus sought to identify the potential targets.

METHODS

Hepatocellular carcinoma cells were exposed to sublethal heat treatment and then cultured with the conditioned medium from activated HSCs (HSC-CM). The cell proliferation, migration, invasion and parameters of epithelial-mesenchymal transition (EMT) were analyzed. In vivo tumor progression of heat-treated residual HCC cells inoculated with activated HSCs was studied in nude mice.

RESULTS

HSC-CM significantly enhanced the proliferation, motility, invasion, prominent EMT activation and decreased apoptosis of heat-exposed residual HCC cells. These increased malignant phenotypes were markedly attenuated by neutralizing periostin (POSTN) in HSC-CM. Furthermore, exogenous POSTN administration exerted the similar effects of HSC-CM on heat-treated residual HCC cells. POSTN induced the prominent activation of p52Shc and ERK1/2 via integrin β1 in heat-exposed residual HCC cells. Vitamin D analog calcipotriol blocked POSTN secretion from activated HSCs. Calcipotriol plus cisplatin significantly suppressed the activated HSCs-enhanced tumor progression of heat-treated residual HCC cells via the inhibited POSTN expression and the increased apoptosis.

CONCLUSIONS

Activated HSCs promote the tumor progression of heat-treated residual HCC through the release of POSTN, which could be inhibited by calcipotriol. Calcipotriol plus cisplatin could be used to thwart the accelerated progression of residual HCC after suboptimal heat treatment.

No-touch multibipolar radiofrequency ablation vs. surgical resection for solitary hepatocellular carcinoma ranging from 2 to 5 cm

BACKGROUND & AIMS

No-touch multibipolar radiofrequency ablation (NTM-RFA) represents a novel therapy that surpasses standard RFA for hepatocellular carcinoma (HCC), but it has not been compared to surgical resection (SR). We aimed to compare the outcomes of NTM-RFA and SR for intermediate-sized HCC.

METHODS

Between 2012 and 2016, 141 patients with solitary HCC ranging from 2 to 5 cm were treated by NTM-RFA or SR at a single-center. The outcomes of 128 patients were compared after using inverse probability of treatment weighting (IPTW).

RESULTS

Seventy-nine patients had NTM-RFA and 62 had SR. After IPTW, the two groups were well-balanced for most baseline characteristics including tumor size, location, etiology, severity of underlying liver disease and alpha-fetoprotein level. Morbidity was higher (67.9% vs. 50.0%, p = 0.042) and hospital stay was longer (12 [IQR 8-13] vs. 7 [IQR 5-9] days, p <0.001) after SR. Local recurrence rates at one and three years were 5.5% and 10.0% after NTM-RFA and 1.9% and 1.9% after SR, respectively (p = 0.065). The rates of systematized recurrence (within the treated segment or in an adjacent segment within a 2 cm distance from treatment site) were higher after NTM-RFA (7.4% vs. 1.9% at one year, 27.8% vs. 3.3% at three years, p = 0.008). Most patients with recurrence were eligible for rescue treatment, resulting in similar overall survival (86.7% after NTM-RFA, 91.4% after SR at three years, p = 0.954) and disease-free survival (40.8% after NTM-RFA, 56.4% after SR at three years, p = 0.119).

CONCLUSION

Compared to SR, NTM-RFA for solitary intermediate-sized HCC was associated with less morbidity and more systematized recurrence, while the rate of local recurrence was not significantly different. Most patients with intrahepatic recurrence remained eligible for rescue therapies, resulting in equivalent long-term oncological results after both treatments.

LAY SUMMARY

Outcomes of patients treated for intermediate-sized hepatocellular carcinoma by surgical resection or no-touch multibipolar radiofrequency ablation were compared. No-touch multibipolar radiofrequency ablation was associated with a lower overall morbidity and a higher rate of systematized recurrence within the treated segment or in an adjacent segment within a 2 cm distance from the initial tumor site. Most patients with intrahepatic recurrence remained eligible for rescue curative therapy, enabling them to achieve similar long-term oncological results after both treatments.

Laser ablation is superior to TACE in large-sized hepatocellular carcinoma: a pilot case-control study

Background

Limited therapies are available for large (≥40 mm) unresectable hepatocellular carcinoma (HCC). Currently, the standard treatment with transarterial chemoembolisation (TACE) is unsatisfactory with high recurrence rate and limited effect on survival. Laser Ablation (LA) has emerged as a relatively new technique characterized by high efficacy and good safety. This study is aimed to evaluate the efficacy of LA in comparison to TACE in patients with large HCC.

Methods

Eighty-two patients with a single HCC nodule ≥40 mm (BCLC stage A or B) were enrolled in this case-control study. Forty-one patients were treated with LA and 41 patients were treated with TACE. Response to therapy was evaluated according to the mRECIST criteria. Survival was calculated with Kaplan-Meier from the time of cancer diagnosis to death with values censored at the date of the last follow-up.

Results

Twenty-six (63.4%) and 8 (19.5%) patients had a complete response after LA and TACE, respectively (p < 0.001). Subsequently we stratified the HCCs in 3 categories according to the nodule size: 40–50 mm, 51–60 mm, and >60 mm. LA resulted superior to TACE especially in nodules ranging between 51 and 60 mm in diameter, with a complete response rate post-LA and post-TACE of 75% and 14.3%, respectively (p = 0.0133). The 36 months cumulative survival rate in patients treated with LA and TACE was 55.4% and 48.8%, respectively. The disease recurrence rates after LA and TACE were 19.5% and 75.0%, respectively.

Conclusions

LA is a more effective therapeutic option than TACE in patients with solitary large HCC.

Percutaneous treatment of hepatocellular carcinoma: State of the art and innovations

Percutaneous treatment of hepatocellular carcinoma (HCC) encompasses a vast range of techniques, including monopolar radiofrequency ablation (RFA), multibipolar RFA, microwave ablation, cryoablation and irreversible electroporation. RFA is considered one of the main curative treatments for HCC of less than 5 cm developing on cirrhotic liver, together with surgical resection and liver transplantation. However, controversies exist concerning the respective roles of ablation and liver resection for HCC of less than 3 to 5 cm on cirrhotic liver. In line with the therapeutic algorithm of early HCC, percutaneous ablation could also be used as a bridge to liver transplantation or in a sequence of upfront percutaneous treatment, followed by transplantation if the patient relapses. Moreover, several innovations in ablation methods may help to efficiently treat early HCC, initially considered as "non-ablatable", and might, in some cases, extend ablation criteria beyond early HCC, enabling treatment of more patients with a curative approach.

Clinical utility of multipolar ablation with a 3-D simulator system for patients with liver cancer

BACKGROUND AND AIM

The aim of this study is to confirm the efficacy of multipolar ablation with a new simulator system, three-dimensional (3-D) sim-Navigator, for patients with hepatocellular carcinoma by assessing relapse-free survival and shape of the ablation volume under clinical conditions.

METHODS

All participants provided written, informed consent, and study protocols were approved by the institutional ethics committee. Twenty-seven patients with 27 nodules were treated by no-touch ablation using the new simulator system. Another 21 patients with 21 nodules treated without the simulator system were enrolled as controls. Tumor progression and shape of ablation volume were assessed. Predictors of tumor progression were assessed by Cox proportional hazard model.

RESULTS

No significant differences in clinical characteristics were seen between groups. Mean sphericity was 0.48 ± 0.07 with 3-D sim-Navigator and 0.37 ± 0.07 without 3-D sim-Navigator (P < 0.001). Median surface-to-volume ratio and compactness were also significantly closer to those of a sphere with 3-D sim-Navigator (P = 0.017, P < 0.001). Relapse-free survival rates at 1 and 1.5 years were 94.1% and 82.4%, respectively, with 3-D sim-Navigator, compared with 83.2% and 55.5% without (P = 0.056). The only independent factor predicting relapse-free survival was use of 3-D sim-Navigator (hazard ratio, 0.12; 95%CI, 0.01-0.87; P = 0.035).

CONCLUSIONS

Ideal ablation area was acquired by this simulation and navigation system in clinics. This system improved local tumor progression by facilitating appropriate insertion of multiple electrodes.

Management consensus guideline for hepatocellular carcinoma: 2016 updated by the Taiwan Liver Cancer Association and the Gastroenterological Society of Taiwan

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality in Taiwan. To help clinical physicians to manage patients with HCC, the Taiwan Liver Cancer Association and the Gastroenterological Society of Taiwan produced the management consensus guideline for HCC.

METHODS

The recommendations focus on nine important issues on management of HCC, including surveillance, diagnosis, staging, surgery, local ablation, transarterial chemoembolization/transarterial radioembolization/hepatic arterial infusion chemotherapy, systemic therapy, radiotherapy, and prevention.

RESULTS

The consensus statements were discussed, debated and got consensus in each expert team. And then the statements were sent to all of the experts for further discussion and refinement. Finally, all of the experts were invited to vote for the statements, including the level of evidence and recommendation.

CONCLUSION

With the development of the management consensus guideline, HCC patients could benefit from the optimal therapeutic modality.

Increased matrix stiffness promotes tumor progression of residual hepatocellular carcinoma after insufficient heat treatment

Aggravated behaviors of hepatocellular carcinoma (HCC) will occur after inadequate thermal ablation. However, its underlying mechanisms are not fully understood. Here, we assessed whether the increased matrix stiffness after thermal ablation could promote the progression of residual HCC. Heat‐treated residual HCC cells were cultured on tailorable 3D gel with different matrix stiffness, simulating the changed physical environment after thermal ablation, and then the mechanical alterations of matrix stiffness on cell phenotypes were explored. Increased stiffness was found to significantly promote the proliferation of the heat‐treated residual HCC cells when the cells were cultured on stiffer versus soft supports, which was associated with stiffness‐dependent regulation of ERK phosphorylation. Heat‐exposed HCC cells cultured on stiffer supports showed enhanced motility. More importantly, vitamin K1 reduced stiffness‐dependent residual HCC cell proliferation by inhibiting ERK phosphorylation and suppressed the in vivo tumor growth, which was further enhanced by combining with sorafenib. Increased matrix stiffness promotes the progression of heat‐treated residual HCC cells, proposing a new mechanism of an altered biomechanical environment after thermal ablation accelerates HCC development. Vitamin K1 plus sorafenib can reverse this protumor effect.

Percutaneous Dual-Switching Monopolar Radiofrequency Ablation Using a Separable Clustered Electrode: A Preliminary Study

Objective

To prospectively evaluate the safety and therapeutic effectiveness of dual-switching monopolar (DSM) radiofrequency ablation (RFA) for the treatment of hepatocellular carcinoma (HCC), and to retrospectively compare the results with those of single-switching monopolar (SSM) RFA in a historical control group.

Materials and Methods

This study was approved by the Institutional Review Board, with informed consent obtained from all patients. Fifty-two HCC patients who underwent DSM-RFA using a separable clustered electrode and dual-generators were prospectively enrolled. Technical parameters, complications, technical success, technical effectiveness, and local tumor progression (LTP) rates were evaluated by means of post-procedural and follow-up imaging. Thereafter, the outcome of DSM-RFA was compared with those of 249 retrospectively included HCC patients treated with SSM-RFA.

Results

There were two major complications (3.8%, 2/52) including pleural and pericardial effusion in the DSM-RFA group. The DSM-RFA yielded a 100% technical success rate, a 98.1% technical effectiveness rate, and a 4.3% 2-year LTP rate. In a retrospective comparison between the two groups, DSM-RFA created significantly larger ablation volume (4.20 ± 2.07 cm³/min vs. 3.03 ± 1.99 cm³/min, p < 0.01), and delivered higher energy (1.43 ± 0.37 kcal/min vs. 1.25 ± 0.50 kcal/min, p < 0.01) per given time, than SSM-RFA. There was no significant difference in major procedure-related complications (3.8% vs. 4.4%) and technical effectiveness rate (98.1% vs. 96.4%) between the two groups (p = 1.00). In addition, the 2-year LTP rate of DSM-RFA and SSM-RFA were 4.3% and 10.1%, respectively (p = 0.15).

Conclusion

DSM-RFA using a separable clustered electrode is safe and provides high local tumor control and good preliminary clinical outcome for small HCCs, which are at least comparable to those of SSM-RFA.

Multipolar versus monopolar radiofrequency ablation for hepatocellular carcinoma in the caudate lobe: Results of a propensity score analysis

AIM

This study aimed to compare multipolar radiofrequency ablation (RFA) with monopolar RFA as the major treatment for nodules of hepatocellular carcinoma in the caudate lobe.

METHODS

This retrospective study was approved by the institutional review board. Data were reviewed from 101 patients who met the Milan criteria and were treated by multipolar RFA (n = 22) or monopolar RFA (n = 79). After propensity score matching, complications and local tumor progression were compared between the two groups.

RESULTS

Before propensity score matching (n = 101), the 2-year relapse-free survival rates for multipolar and monopolar RFA (65.1% vs. 38.8%, respectively; P = 0.064) and the local tumor progression rate (12.5% vs. 14.9%, respectively; P = 0.313) were not significantly different. There were no significant differences between the two RFA techniques by treatment efficacy of transcatheter hepatic arterial embolization, location of tumor, and puncture route. After matching (n = 44), the 2-year relapse-free survival rate for the multipolar and monopolar groups (65.1% vs. 22.7%, respectively; P = 0.004) was significantly different, and the local tumor progression rate (12.5% vs. 22.9%, respectively; P = 0.004) was significantly different. No severe complications occurred in the patients treated by multipolar RFA.

CONCLUSION

Multipolar RFA appears to be a safe and effective method for hepatocellular carcinoma nodules in the caudate lobe.

Radiofrequency ablation of hepatocellular carcinoma as bridge therapy to liver transplantation: A 10-year intention-to-treat analysis

In a long-term (10-year) study of radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) as bridging therapy in patients listed for orthotopic liver transplantation (LT), we evaluated the impact of RFA on waiting list dropout rate, post-LT tumor recurrence, and long-term intention-to-treat, disease-specific survival (DSS). From March 2004 to October 2014, RFA was performed as the initial stand-alone bridge therapy to LT for 121 patients (men/women ratio, 83:38; mean age, 60.0 years) with 156 de novo HCCs (mean size, 2.4 cm). Follow-up period from initial RFA ranged from 1.3 to 128.0 months (median, 42.9 months). We assessed the overall and tumor-specific waiting list dropout rates, post-LT tumor recurrence, and 10-year post-LT and intention-to-treat survival rates. Dropout from the waiting list due to tumor progression occurred in 7.4% of patients. HCC recurrence after LT occurred in 5.6% of patients. The post-LT overall survival (OS) rate at 5 and 10 years was 75.8% and 42.2%, respectively, and the recurrence-free survival (RFS) rate was 71.1% and 39.6%, respectively. Intention-to-treat OS, RFS, and DSS rates for the entire study population at 5 and 10 years were 63.5% and 41.2%, 60.8% and 37.7%, and 89.5% and 89.5%, respectively.

CONCLUSION

RFA as a first-line stand-alone bridge therapy to LT achieves excellent long-term overall and tumor-specific survivals, with a low dropout rate from tumor progression despite long wait list times and a sustained low tumor recurrence rate upon post-LT follow-up of up to 10 years. (Hepatology 2017;65:1979-1990).

Activated hepatic stellate cells secrete periostin to induce stem cell-like phenotype of residual hepatocellular carcinoma cells after heat treatment

Some evidences show that residual tumor after thermal ablation will progress rapidly. However, its mechanisms remain unclear. Here, we assessed whether activated HSCs could regulate stem cell-like property of residual tumor after incomplete thermal ablation to promote tumor progression. Human HCC cell lines were exposed to sublethal heat treatment to simulate the peripheral zone of thermal ablation. After residual HCC cells were cultured with conditional medium (CM) from activated HSCs, parameters of the stem cell-like phenotypes were analyzed. Nude mice bearing heat-exposed residual HCC cells and HSCs were subjected to metformin treatment to thwarter tumor progression. CM from activated primary HSCs or LX-2 cells significantly induced the stem cell-like phenotypes of residual HCC cells after heat treatment. These effects were significantly abrogated by neutralizing periostin (POSTN) in the CM. POSTN regulated the stemness of heat-exposed residual HCC cells via activation of integrin β1/AKT/GSK-3β/β-catenin/TCF4/Nanog signaling pathway. Metformin significantly inhibited in vivo progression of heat-exposed residual HCC via suppressing POSTN secretion and decreasing cancer stem cell marker expression. Our data propose a new mechanism of activated HSCs promoting the stemness traits of residual HCC cells after incomplete thermal ablation and suggest metformin as a potential drug to reverse this process.

Transarterial chemoembolization for early stage hepatocellular carcinoma decrease local tumor control and overall survival compared to radiofrequency ablation

BACKGROUND & AIMS

To compare treatment failure and survival associated with ultrasound-guided radiofrequency ablation (RFA) and trans-arterial chemoembolization (TACE) for early-stage HCC in Child-Pugh A cirrhosis patients.

METHODS

122 cirrhotic patients (RFA: 61; TACE: 61) were well matched according to cirrhosis severity; tumor size and serum alpha-fetoprotein. TACE was performed in case of inconspicuous nodule on US or nodule with "at risk location". Treatment failure was defined as local tumor progression (LTP) and primary treatment failure (failing to obtain complete response after two treatment session). Treatment failure and overall survival (OS) were compared after coarsened exact matching. Cox proportional model to assess independent predictive factors was performed.

RESULTS

No significant difference was seen for baseline characteristics between the two groups. Mean tumor size was 3cm in both group with 41% HCC>3cm. Treatment failure rates after TACE was 42.6% (14 primary treatment failures and 12 LTP) and 9.8% after RFA (no primary treatment failure and 6 LTP) P < 0.001. TACE was the only predictive factor of treatment failure (Hazard ratio: 5.573). The 4-years OS after RFA and TACE were 54.1% and 31.5% (P = 0.042), respectively.

CONCLUSION

For Child-Pugh A patients with early-stage HCC, alternative treatment as supra-selective TACE to RFA regarded as too challenging using common US guidance decrease significantly the local tumor control and overall survival. Efforts to improve feasibility of RFA especially for inconspicuous target have to be made.

Comparison of no-touch multi-bipolar vs. monopolar radiofrequency ablation for small HCC

BACKGROUND & AIMS

The primary aim of this study was to compare the rate of global radiofrequency ablation (RFA) failure between monopolar RFA (MonoRFA) vs. no-touch multi-bipolar RFA (NTmbpRFA) for small hepatocellular carcinoma (HCC) ⩽5cm in cirrhotic patients.

METHODS

A total of 362 cirrhotic patients were included retrospectively across four French centres (181 per treatment group). Global RFA failure (primary RFA failure or local tumour progression) was analysed using the Kaplan-Meier method after coarsened exact matching. Cox regression models were used to identify factors associated with global RFA failure and overall survival (OS).

RESULTS

Patients were well matched according to tumour size (⩽30/>30mm); tumour number (one/several); tumour location (subcapsular and near large vessel); serum AFP (<10; 10-100; >100ng/ml); Child-Pugh score (A/B) and platelet count (</⩾100G/L), p=1 for all. One case of perioperative mortality was observed in the NTmbpRFA group and the rate of major complications was 7.2% in both groups (p=1). The cumulative rates of global RFA failure at 1, 3 and 5years were respectively 13.3%, 31% and 36.7% for MonoRFA vs. 0.02%, 7.9% and 9.2% for NTmbpRFA, p<0.001. Monopolar RFA, tumour size >30mm and HCC near large vessel were independent factors associated with global RFA failure. Five-year OS was 37.2% following MonoRFA vs. 46.4% following NTmbpRFA p=0.378.

CONCLUSIONS

This large multicentre case-matched study showed that NTmbpRFA provided better primary RFA success and sustained local tumour response without increasing severe complications rates, for HCC ⩽5cm.

LAY SUMMARY

Using no-touch multi-bipolar radiofrequency ablation for hepatocellular carcinoma ⩽5cm provide a better sustained local tumour control compared to monopolar radiofrequency ablation.

Quick and stable parallel puncture of hepatic tumors using a double-barreled needle direction system for ultrasound-guided bipolar radiofrequency ablation

AIM

In bipolar radiofrequency ablation (RFA) therapy, insertion of multiple needles at appropriate points on a target is difficult. The aim of our study was to evaluate a simplified method for multi-electrode insertion using a newly developed double-barreled needle guidance system for percutaneous RFA of hepatic tumors.

METHODS

RFA using two bipolar electrodes was performed in 15 consecutive patients (nine men, six women; mean age, 72.0 ± 8.2 years) with a solitary small (≤3 cm) hepatic tumor. The first five nodules were treated using the conventional puncture method with the standard attachment, then 10 nodules were ablated using the parallel puncture method with the double-barreled attachment. The times required for double-needle placement and the shapes of the ablated areas were compared between the two puncture methods.

RESULTS

The parallel puncture method required a shorter time for double-needle placement than the conventional method (12 s [range, 8-24] vs 96 s [range, 50-240]; P = 0.0003), and allowed continuous observation of the tip of all needles and the size of the ablated area as it increased until completion of the ablation. The method also provided a stable ellipsoidal ablated area. The median height, width and thickness were 30 mm (range, 22-34), 30 mm (range, 21-33) and 20 mm (range, 7-25), respectively, using 20-mm electrodes, and 34 mm (range, 32-41), 36 mm (range, 35-38) and 24 mm (range, 23-24), respectively, using 30-mm electrodes.

CONCLUSION

The parallel puncture method may be a feasible procedure for multi-needle RFA therapy.

Microwave Ablation Using Four-Tine Antenna: Effects of Blood Flow Velocity, Vessel Location, and Total Displacement on Porous Hepatic Cancer Tissue

This research is concerned with microwave ablation analyses using a 2.45 GHz four-tine (4T) antenna for hepatic cancer tissue. In the study, three-dimensional finite-element models were utilized to examine the tissue temperature distributions during and after MW ablation. A preliminary study was first carried out with regard to the specific absorption rates along the 4T antenna insertion depths and the temperature distributions inside the solid and porous liver models with either 3 cm-in-diameter tumor or 5 cm-in-diameter tumor. Based on the preliminary results, the porous models were further examined for the effect of varying blood flow velocities (0–200 cm/s) with a 1 cm-in-diameter blood vessel next to the antenna and also for the effect of vessel-antenna locations (0, 0.8, and 1.3 cm) with a constant blood flow velocity of 16.7 cm/s. All scenarios were simulated under temperature-controlled mode (90°C). The findings revealed that the blood flow velocity and vessel location influence the ablation effectiveness and that increased blood flow inhibits heat transfer to the vessel wall. At the nearest and farthest vessel-antenna locations (0 and 1.3 cm), approximately 90.3% and 99.55% of the cancer cells were eradicated except for the areas adjacent to the vessel. In addition, total tissue thermal displacement is 5.9 mm which is 6.59% of the total length of the overall model.

Assessment of a needle-tracking system for bipolar radiofrequency ablation

PURPOSE

The purpose of this study was to assess the accuracy and efficacy of a needle-tracking system in phantom and clinical studies using bipolar electrodes.

METHODS

To observe the tip of the electrode, a needle-tracking system with a volume navigation system was used. In the phantom study, the electrode was inserted at various angles and the error was verified. In the clinical study, 21 nodules close to extrahepatic organs or major vessels were enrolled between May and October 2014. After puncturing with the needle-tracking system, computed tomography (CT) was performed. The distances between the electrode tip and extrahepatic organs or major vessels were measured on both B-mode ultrasound (US) and CT. By comparing these distances, the accuracy of this system was evaluated.

RESULTS

In the phantom study, the deviation between the tip of the electrode and the virtual tip of the electrode was analyzed. The median values were within 2 mm at each puncture angle. In the clinical study, the difference between B-mode US and CT was less (mean value 1.17 ± 1.76 mm; range 0-3.5 mm).

CONCLUSION

The needle-tracking system is an accurate and useful system for bipolar radiofrequency ablation.

Radiofrequency ablation of hepatocellular carcinoma: Mono or multipolar?

BACKGROUND AND AIMS

Thermo-ablation by radiofrequency is recognized as a curative treatment for early-stage hepatocellular carcinoma. However, local recurrence may occur because of incomplete peripheral tumor destruction. Multipolar radiofrequency has been developed to increase the size of the maximal ablation zone. We aimed to compare the efficacy of monopolar and multipolar radiofrequency for the treatment of hepatocellular carcinoma and determine factors predicting failure.

METHODS

A total of 171 consecutive patients with 214 hepatocellular carcinomas were retrospectively included. One hundred fifty-eight tumors were treated with an expandable monopolar electrode and 56 with a multipolar technique using several linear bipolar electrodes. Imaging studies at 6 weeks after treatment, then every 3 months, assessed local effectiveness. Radiofrequency failure was defined as persistent residual tumor after two sessions (primary radiofrequency failure) or local tumor recurrence during follow-up. This study received institutional review board approval (number 2014/77).

RESULTS

Imaging showed complete tumor ablation in 207 of 214 lesions after the first session of radiofrequency. After a second session, only two cases of residual viable tumor were observed. During follow-up, there were 46 local tumor recurrences. Thus, radiofrequency failure occurred in 48/214 (22.4%) cases. By multivariate analysis, technique (P < 0.001) and tumor size (P = 0.023) were independent predictors of radiofrequency failure. Failure rate was lower with the multipolar technique for tumors < 25 mm (P = 0.023) and for tumors between 25 and 45 mm (P = 0.082). There was no difference for tumors ≥ 45 mm (P = 0.552).

CONCLUSIONS

Compared to monopolar radiofrequency, multipolar radiofrequency improves tumor ablation with a subsequent lower rate of local tumor recurrence.

Usefulness of a New Three-Dimensional Simulator System for Radiofrequency Ablation

Multipuncture radiofrequency ablation is expected to produce a large ablated area and reduce intrahepatic recurrence of hepatocellular carcinoma; however, it requires considerable skill. This study evaluated the utility of a new simulator system for multipuncture radiofrequency ablation. To understand positioning of multipuncture electrodes on three-dimensional images, we developed a new technology by expanding real-time virtual ultrasonography. We performed 21 experimental punctures in phantoms. Electrode insertion directions and positions were confirmed on computed tomography, and accuracy and utility of the simulator system were evaluated by measuring angles and intersections for each electrode. Moreover, to appropriately assess placement of the three electrodes, puncture procedures with or without the simulator were performed by experts and non-experts. Technical success was defined as maximum angle and distance ratio, as calculated by maximum and minimum distances between electrodes. In punctures using 2 electrodes, correlations between angles on each imaging modality were strong (ultrasound vs. simulator: r = 0.991, p<0.001, simulator vs. computed tomography: r = 0.991, p<0.001, ultrasound vs. computed tomography: r = 0.999, p<0.001). Correlations between distances in each imaging modality were also strong (ultrasound vs. simulator: r = 0.993, p<0.001; simulator vs. computed tomography: r = 0.994, p<0.001; ultrasound vs. computed tomography: r = 0.994, p<0.001). In cases with 3 electrodes, distances between each electrode correlated strongly (yellow-labeled vs. red-labeled: r = 0.980, p<0.001; red-labeled vs. blue-labeled: r = 0.953, p<0.001; yellow-labeled vs. blue-labeled: r = 0.953, p<0.001). Both angle and distance ratio (expert with simulator vs. without simulator; p = 0.03, p = 0.02) were significantly smaller in procedures performed by experts using the simulator system. The new simulator system appears to accurately guide electrode positioning. This simulator system could allow multipuncture radiofrequency ablation to be performed more effectively and comfortably.

The Effectiveness of Multiple Electrode Radiofrequency Ablation in Patients with Hepatocellular Carcinoma with Lesions More than 3 cm in Size and Barcelona Clinic Liver Cancer Stage A to B2

Outcomes of hepatocellular carcinoma (HCC) lesions >3.0 cm in size including Barcelona Clinic Liver Cancer (BCLC) stage B after radiofrequency ablation (RFA) with a single electrode remain unsatisfactory. This study aimed to investigate the outcomes of RFA with multiple electrodes (ME-RFA) for HCC tumors 3.1-7.0 cm in size and BCLC stage B. This retrospective study included 70 consecutive patients with 58 medium- (3.1-5.0 cm) and 17 large- (5.1-7.0 cm) sized HCCs after ME-RFA using a controller. Outcomes in terms of complete response, primary technique effectiveness, local tumor progression, and overall survival were investigated. After 1-4 applications of ME-RFA, the rates of complete response and PTE in medium-sized tumors were 79.3% and 91.4%, respectively, and in large tumors were 76.5% and 94.1%, respectively. Overall, the major complication rate was 5.7%. After a median 21-month follow-up period, both two- and three-year estimated overall survival rates were above 80%. There were no significant differences in overall survival and local tumor progression rates between medium- and large-size tumors and among BCLC stages A, B1 and B2. A complete response to ME-RFA was the only significant factor associated with improved survival (p=0.008). In conclusion, ME-RFA can effectively treat 3.1-7.0-cm sized HCCs with a comparable outcome between medium- and large-size tumors and among BCLA stages A to B2.

Current status and prospective of imaging guided radiofrequency ablation in medium to large sized hepatocellular carcinomas

The incidence of liver cancer is high in China and effective treatments are required. Recently, imaging guided radiofrequency ablation (RFA) has become increasingly accepted in treating solid tumors because of minimal invasiveness, easy operation and effectiveness. The outcome of RFA in small liver tumors is even comparable to that of surgery. However, the RFA efficacy in larger ( > 3.0 cm) liver tumors is not satisfactory and recurrence after treatment is common. The development of basic research and RFA device has provided more opportunities for us to treat>3.0 cm liver tumors. The successful ablation of solid tumors relies on three key components, the technology (i.e., the RFA generator and electrodes selected), the biology of the tumor and background tissue, and operator factors. The current development and prospective of the three main elements will be the focus in this review.

Effectiveness of combined (131)I-chTNT and radiofrequency ablation therapy in treating advanced hepatocellular carcinoma

To investigate the effectiveness of monoclonal antibody ((131)I-chTNT) and radiofrequency ablation (RFA) combination therapy in treating middle-advanced stage hepatocellular carcinoma (HCC). Thirty-four patients diagnosed with HCC patients, divided into two groups comprised of 22 and 12 cases were included in this retrospective study. The two groups received RFA with or without ((131)I-chTNT) therapy, respectively. The patients in these groups were followed up for a median of 31 and 35 months, respectively. Patient survival was evaluated using Kaplan-Meier method and safety profiles were determined by analyzing liver, thyroid, and bone marrow toxicities. This retrospective study showed that survival time of the patients who received combination therapy was significantly longer than that of the RFA group (P = 0.052). The median progress-free survival of patients in the two groups was 23 and 7 months, respectively, and the difference was significant (P = 0.04). Tumor recurred in 3.5-8.7 months in four of the combination group patients, among which three had newly developed lesions. The red blood cells and platelets counts were not altered on day 7 and 1 month of the treatment, however, number of white blood cells was significantly increased on day 7 which was reversed back to the normal range in 2 weeks. The ALT and AST were also not significantly altered on day 7 and 1 month of therapy. In middle-advanced stage HCC patients, the combination of (131)I-chTNT and RFA therapy was found to be significantly more effective than the RFA treatment alone as assessed in short-term follow-up. However, the dose we used was insufficient to completely block the local recurrence of the lesions with a diameter of 5 cm or larger.

[Current management of hepatocellular carcinoma]

Hepatocellular carcinoma is the major complication of chronic liver diseases and particularly of cirrhosis whatever its etiology. Once encountered mainly in the endemic countries of hepatitis B and C, the incidence of hepatocellular carcinoma (6/100,000) is parallel to the global development of diabetes, overweight and alcohol consumption. Little progress has been made for this cancer, whose mortality is 100 % at 10 years. Liver transplantation is the only truly curative treatment (survival more than 50 % at 10 years) since it allows the eradication of hepatocellular carcinoma and its essential cause, cirrhotic liver. This is the only possible therapy when liver function is impaired. It has little impact since in the richest countries, less than 10 % of cases can be transplanted. Surgical resection and percutaneous destruction methods (uni- and multipolar radiofrequency, microwave, cryotherapy, electroporation) are the preferred treatments (survival less than 50 % at 5 years) but are only applicable for moderate tumour masses and in the absence of adjuvant therapy, are effective only in the medium term. Most patients received chemoembolization through hepatic artery, whose action is modest. Radiotherapy is widely used in Asia but almost non-existent in Western countries in this indication. Sorafenib is the only effective drug but its impact is modest. Therapies combining two modalities (embolization and radiotherapy; embolization and radiofrequency) seem promising and deserve wider testing. Screening and monitoring of cirrhosis is probably the major measure for potentially curative therapies.

Impact of current staging systems on treatment strategy for HBV-related hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the second leading cause of cancer-related death worldwide. HCC incidence has increased over the last few years, with more than half of HCC cases being reported in China, where hepatitis B virus (HBV) infection is the main etiologic factor. The heterogeneity in HCC's worldwide distribution and the differences in its etiology in different locations may result in prognosis estimation and therapeutic decision making being more complicated for HCC patients. In the past decade, several clinical staging systems have been developed based on relevant prognostic factors. Among them, the Barcelona Clinic Liver Cancer (BCLC) and Hong Kong Liver Cancer (HKLC) staging systems are the only two classification systems that link prognostic classification to treatment indications. In this review, we mainly focus on the use of the BCLC and HKLC staging systems for guiding therapeutic decision making for HCC, the respective advantages and disadvantages of each classification system, and future perspectives for the improvement of the HKLC model.

Effect of Nonparallel Placement of In-Circle Bipolar Radiofrequency Ablation Probes on Volume of Tissue Ablated With Heat Sink

Objectives. Percutaneous bipolar radiofrequency ablation (RFA) is a minimally invasive technique for treating liver tumors. It is not always possible to insert the bipolar probes parallel to each other on either side of tumor, since it restricts maneuverability away from vital structures or ablate certain tumor shape. Therefore, we investigated how nonparallel placement of probes affected ablation. Methods. Bipolar RFA in parallel and in divergent positions were submerged in tissue model (800 mL egg white) at 37°C and ablated. Temperature probes, T1 and T2 were placed 8.00 mm below the tip of the probes, T3 in between the probe coil elements and T4 and T5 at water inlet and outlet, respectively. Both models with heat sink (+HS) and without (−HS) were investigated. Results. The mean ablated tissue volume, mass, density and height increased linearly with unit angle increase for −HS model. With +HS, a smaller increase in mean volume and mass, a slightly greater increase in mean density but a reduction in height of tissue was seen. The mean ablation time and duration of maximum temperature with +HS was slightly larger, compared with −HS, while −HS ablated at a slightly higher temperature. The heat sink present was minimal for probes in parallel position compared to nonparallel positions. Conclusion. Divergence from parallel insertion of bipolar RFA probes increased the mean volume, mass, and density of tissue ablated. However, the presence of large heat sinks may limit the application of this technique, when tumors border on larger vessels.

Percutaneous hepatic radiofrequency for hepatocellular carcinoma: results and outcome of 46 patients

Radiofrequency ablation (RFA) is a curative option for hepatocellular carcinoma (HCC), the most common primary malignancy of the liver. This bicentric retrospective study includes 46 patients admitted for their first percutaneous RFA for HCC. Sixty-three nodules were treated, with an average size of 32.5 mm. Our study confirms the efficiency of this technique for attaining necrosis of HCC nodules, with few complications. Subgroup studies according to RFA mode (mono- or multipolar), etiology of cirrhosis (alcoholic or viral), and HCC size showed better efficiency for multipolar RFA when applied to small tumors and better survival when the cirrhosis was due to viral infection. However, we noted a high rate of local recurrence in our and other recent works compared to previous studies, probably due to improved imaging techniques. The main problem is still de novo intrahepatic recurrence in diseased livers.