Radiofrequency ablation for hepatocellular carcinoma in so-called high-risk locations

Safety assessment and therapeutic efficacy of percutaneous microwave ablation therapy combined with percutaneous ethanol injection for hepatocellular carcinoma adjacent to the gallbladder

OBJECTIVE

This study sought to evaluate the safety and efficacy of ultrasound-guided (US-guided) percutaneous microwave (MW) ablation combined with percutaneous ethanol injection (PEI) to treat liver tumours adjacent to the gallbladder.

MATERIALS AND METHODS

A total of 136 patients with hepatocellular carcinoma (HCC) adjacent to the gallbladder, who underwent ultra-sonographically-guided percutaneous MW ablation, which was combined with PEI in 132 patients, were retrospectively assessed. The patient population characteristics, tumour features, local tumour progression and treatment were compared and analysed. The safety and efficacy of the therapy were assessed by clinical data and imaging in follow-up examinations.

RESULTS

All patients were completely treated with two sessions; 120 patients underwent one session, 16 patients underwent two sessions. The primary technique was effective in 95.6% of the cases, according to the computed tomography (CT) or magnetic resonance imaging (MRI) in the one-month follow-up (132 of 138 sessions). PEI and other therapies were performed in the patients who had been incompletely treated (all six patients underwent PEI, and some underwent other therapies, including one transcatheter arterial chemoembolisation (TACE), one liver transplantation and two liver resections). There was a median follow-up period of 30.1 months and a range of 4 to 68 months. None of the patients had major complications. There were no treatment-related deaths. Twenty-six patients died of primary disease progression that was not directly attributable to MW ablation (19.1%, 26/136). Local tumour progression was noted in five patients (3.7%, 5/136), who had completely ablated tumours at follow-up. The patients with locally progressing tumours underwent additional therapy (three patients underwent PEI, one patient TACE, and one liver resection).

CONCLUSION

Ultrasound-guided percutaneous MW ablation, in combination with percutaneous ethanol injection and thermal monitoring, is a safe and effective treatment for HCC adjacent to the gallbladder.

An overview of loco-regional treatments in patients and mouse models for hepatocellular carcinoma

Hepatocellular carcinoma is a highly aggressive malignancy and is the third leading cause of cancer-related deaths worldwide. Although surgery is currently considered the most effective curative treatment for this type of cancer, it is note that most of patients have a poor prognosis due to chemioresistence and tumor recurrence. Loco-regional therapies, including radiofrequency ablation, surgical resection and transcatheter arterial chemoembolization play a major role in the clinical management of hepatocellular carcinoma. In order to improve the treatment outcome of patients diagnosed with this disease, several in vivo studies by using different techniques on cancer mouse models have been performed. This review will focus on the latest papers on the efficacy of loco-regional therapy and combined treatments in patients and mouse models of hepatocellular carcinoma.

Radiofrequency ablation versus laser ablation for the treatment of small hepatocellular carcinoma in cirrhosis: a randomized trial

BACKGROUND AND AIM

In patients with cirrhosis and small hepatocellular carcinoma (HCC), thermal ablation is currently recognized as an effective local treatment. Among thermal procedures, radiofrequency ablation (RFA) is the most diffusely used and is the standard against which any new treatment should be compared. In retrospective studies, laser ablation (LA) resulted as safe and effective as RFA. Therefore, we performed a non-inferiority randomized trial comparing RFA with LA in patients with cirrhosis and HCC within Milan criteria.

METHODS

Overall, 140 patients with 157 HCC nodules were randomly assigned to receive RFA or LA. The primary end-point was the proportion of complete tumor ablation (CTA). Secondary end-points were time to local progression (TTLP) and overall survival (OS).

RESULTS

Per patient CTA rates after RFA and LA were 97.4% (95% CI, 91.0-99.3) and 95.7% (88.1-98.5), respectively (difference = 1.4%, 95% CI from -6.0% to + 9.0%). Per nodule CTA rates for RFA and LA were 97.4% (91.0-99.3) and 96.3% (89.6-98.7), respectively (difference = 1.1%, from -5.7% to + 8.1%). The mean TTLP was comparable between RFA group (42.0 months; 95% CI, 36.83-47.3) and LA group (46.7 months; 95% CI, 41.5-51.9) (P = .591). The mean OS was 42 months in both groups and survival probability at 1 and 3 years was 94% and 89% in RFA group, and 94% and 80% in LA group.

CONCLUSION

LA resulted not inferior to RFA in inducing the CTA of HCC nodules and therefore it should be considered as an evaluable alternative for thermal ablation of small HCC in cirrhotic patients.

Radiofrequency ablation of hepatocellular carcinoma in difficult locations: Strategies and long-term outcomes

AIM: To investigate the treatment strategies and long-term outcomes of radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) in difficult locations and to compare the results with non-difficult HCC.

METHODS: From 2004 to 2012, a total of 470 HCC patients underwent ultrasound-guided percutaneous RFA. Among these HCC patients, 382 with tumors located ≤ 5 mm from a major vessel/bile duct (n = 87), from peripheral important structures (n = 232) or from the liver capsule (n = 63) were regarded as difficult cases. There were 331 male patients and 51 female patients, with an average age of 55.3 ± 10.1 years old. A total of 235 and 147 patients had Child-Pugh class A and class B liver function, respectively. The average tumor size was 3.4 ± 1.2 cm. Individual treatment strategies were developed to treat these difficult cases. During the same period, 88 HCC patients with tumors that were not in difficult locations served as the control group. In the control group, 74 patients were male, and 14 patients were female, with an average age of 57.4 ± 11.8 years old. Of these, 62 patients and 26 patients had Child-Pugh class A and class B liver function, respectively. Regular follow-up after RFA was performed to assess treatment efficacy. Survival results were generated from Kaplan-Meier estimates, and multivariate analysis was performed using the Cox regression model.

RESULTS: Early tumor necrosis rate in the difficult group was similar to that in the control group (97.6% vs 94.3%, P = 0.080). The complication rate in the difficult group was significantly higher than that in the control group (4.9% vs 0.8%, P = 0.041). The follow-up period ranged from 6 to 116 mo, with an average of 28 ± 22.4 mo. Local progression rate in the difficult group was significantly higher than that in the control group (12.7% vs 7.1%, P = 0.046). However, the 1-, 3-, 5-, and 7-year overall survival rates in the difficult group were not significantly different from those in the control group (84.3%, 54.4%, 41.2%, and 29.9% vs 92.5%, 60.3%, 43.2%, and 32.8%, respectively, P = 0.371). Additionally, a multivariate analysis revealed that tumor location was not a significant risk factor for survival.

CONCLUSION: There was no significant difference in long-term overall survival between the two groups even though the local progression rate was higher in the difficult group.

[Percutaneous ablation of hepatocellular carcinoma in older patients in clinical practice]

INTRODUCTION

A high percentage of older patients with early-stage hepatocellular carcinoma (HCC) are potential candidates for percutaneous ablation.

MATERIAL AND METHODS

We prospectively assessed data from patients older than 70 years with HCC. We determined their demographic and clinical characteristics, the treatment provided and the response, complications and survival among those treated with radiofrequency ablation (RFA) and/or percutaneous ethanol injection (PEI).

RESULTS

Of 194 patients with HCC, 84 were older than 70 years (43.3%). The mean age was 76.8 ± 4.5 years. Seventy-five percent were male and 91.7% had cirrhosis. Cancer was initially identified by a surveillance program in 61.9%. According to the Barcelona Clinic Liver Cancer staging system, 60.7% were classified as having early stage cancer (0-A), 19% as stage B, 12% as stage C, and 8.3% as stage D. Potentially curative initial treatment was provided in 38.2% (surgical resection in 4.8%, PEI in 22.6%, RFA in 4.8%, PEI+RFA in 6%), transarterial chemoembolization in 20.2%, and sorafenib in 3.6%. Twenty-five percent of patients were not treatment candidates and 13% refused the recommended treatment. The median follow-up after percutaneous ablation was 23 months (IQR 14.2-40.6). The mean number of sessions was 3.5 ± 2.2 for PEI and 1.8 ± 1.6 for RFA. The complications rate per session was 4%. Remission was achieved in 35.7%. The overall median survival was 45.7 months (95% CI 20.8-70.6).

CONCLUSIONS

Almost half of the patients with HCC in our sample were elderly and more than half were diagnosed at an early stage. Percutaneous ablation was performed in one-third of the sample, achieving remission in 37.5%. There were few complications. Therefore, these patients should be assessed for percutaneous ablation.

Management of “very early” hepatocellular carcinoma on cirrhotic patients

Due to the advances in screening of cirrhotic patients, hepatocellular carcinoma (HCC) is being diagnosed in earlier stages. For this reason the number of patients diagnosed of very early HCC (single tumors ≤ 2 cm) is continuously increasing. Once a patient has been diagnosed with this condition, treatment strategies include liver resection, local therapies or liver transplantation. The decision on which therapy should the patient undergo depends on the general patients performance status and liver disease. Anyway, even in patients with similar conditions, the best treatment offer is debatable. In this review we analyze the state of the art on the management of very early HCC on cirrhotic patients to address the best treatment strategy for this patient population.

Various complications of percutaneous radiofrequency ablation for hepatic tumors: radiologic findings and technical tips

Radiofrequency ablation is a safe and effective treatment for primary and secondary liver malignancies and has a low complication rate; however, there are various radiofrequency ablation-related complications which can occur from the thorax to the pelvis. Although most of these complications are usually minor and self-limited, they may become fatal if diagnosis and treatment are delayed. It is important for radiologists performing radiofrequency ablation to have a perspective regarding the possible radiofrequency ablation-related complications and their risk factors as well as the radiologic findings for their timely detection and increase of the treatment efficacy, and thereby encouraging the use of the radiofrequency ablation technique. This article illustrates the various imaging features of common and rare radiofrequency ablation-related complications as well as offers technical tips in order to avoid these complications.

Laser ablation for small hepatocellular carcinoma: State of the art and future perspectives

During the last two decades, various local thermal ablative techniques for the treatment of unresectable hepatocellular carcinoma (HCC) have been developed. According to internationally endorsed guidelines, percutaneous thermal ablation is the mainstay of treatment in patients with small HCC who are not candidates for surgical resection or transplantation. Laser ablation (LA) represents one of currently available loco-ablative techniques. In this article, the general principles, technique, image guidance, and patient selection are reported. Primary effectiveness, long-term outcome, and complications are also discussed. A review of published data suggests that LA is equivalent to the more popular and widespread radiofrequency ablation in both local tumor control and long-term outcome in the percutaneous treatment of early HCC. In addition, the LA technique using multiple thin laser fibres allows improved ablative effectiveness in HCCs greater than 3 cm. Reference centres should be equipped with all the available techniques so as to be able to use the best and the most suitable procedure for each type of lesion for each patient.

A case of small hepatocellular carcinoma treated with laparoscopic multipolar radiofrequency ablation with a no-touch ablation procedure

A 77-year-old man with hepatocellular carcinoma was admitted to our institution. Computed tomography revealed two nodules, one at the surface and one within the liver, ≤3 cm in diameter. We performed laparoscopic radiofrequency ablation using a bipolar system with a "no-touch ablation" procedure using multiple applicators for insertion, not into the tumor directly, but to the perimeter of the tumor. A sufficient ablated area was obtained regardless of tumor location. No operative complications were encountered and adequate therapeutic effect was achieved safely. Laparoscopic multipolar radiofrequency ablation is a feasible procedure for treating hepatocellular carcinoma.

Cause-specific mortality associated with aging in patients with hepatocellular carcinoma undergoing percutaneous radiofrequency ablation

OBJECTIVE

The number of elderly patients diagnosed with hepatocellular carcinoma (HCC) is expected to increase. The aim of this study is to evaluate the efficacy of radiofrequency ablation (RFA) in elderly patients with HCC and to investigate cause-specific excess deaths associated with increasing number of elderly patients.

MATERIALS AND METHODS

We enrolled 1401 naive patients with HCC who were treated initially by RFA from 1999 to 2011. Patients below 75 years of age were categorized as 'younger' and those at least 75 as 'elderly'. Differences in the demographic and laboratory data of these patients were assessed, along with Kaplan-Meier analysis of survival using the log-rank test. In addition, we assessed the causes of death, defined as liver related and liver unrelated, by competing risk analysis and risk factors for respective causes of death by a proportional subdistribution model.

RESULTS

Overall, 353 patients were categorized as elderly. Elderly patients were more likely to be women, infected with hepatitis C virus, and score better in the Child-Pugh classification. The mortality at 5 years was lower in the elderly than in the younger patients (47.3 vs. 37.1%; P<0.001). Competing risk analysis showed a significant difference in liver-unrelated death (P<0.001) between the two groups, whereas there were no significant differences in liver-related death (P=0.64). By the proportional subdistribution model, age was a significant risk factor only for liver-unrelated death.

CONCLUSION

RFA provided satisfactory 5-year survival rates in elderly patients with HCC. The elderly tended to die from liver-unrelated causes.

Radiofrequency thermoablation of HCC larger than 3 cm and less than 5 cm proximal to the gallbladder without gallbladder isolation: a single center experience

Radiofrequency ablation (RFA) is an effective minimally invasive treatment for nonsurgical hepatocellular carcinoma (HCC), but ablation of tumors close to the gallbladder could be associated with several complications. We report our experience on the treatment of HCC close to the gallbladder with RFA. Eight RFA procedures were performed in eight patients with HCC larger than 3 cm and less than 5 cm close to the gallbladder. In all cases, a percutaneous approach was used. There were no major complications. Only in two patients a minimal wall thickening of the gallbladder was observed. Contrast enhanced computed tomography carried out after 30 days from the first procedure showed complete necrosis in seven patients (87%). Only one patient had local recurrence at 11 months of followup. Although limited, our experience suggests that, after careful preprocedural planning, in experienced hands and with appropriate technology, percutaneous RFA could be safely performed even for lesions larger than 3 cm located in close adjacency to the gallbladder.

Radiofrequency ablation of liver VX2 tumor: experimental results with MR diffusion-weighted imaging at 3.0T

PURPOSE

To evaluate the value of DWI in detecting the lesions of pre- and post-radiofrequency ablation (RFA) of the rabbit liver VX2 tumors.

MATERIALS AND METHODS

Twenty-two New Zealand White rabbits were tested. The protocol was approved by the Committee on the Ethics of Animal Experiments. Twenty separate tumor fragments were implanted into the livers of 20 rabbits, the liver was exposed by performing midline laparotomy. 3.0T MR DWI (b = 0, 200, 400, 600, 800,1000 s/mm2) were performed 14-21 days after tumor implantation (mean, 17 days) in the 18 tumor-bearing animals. Then RFA was performed in the 18 tumor-bearing animals and in the two healthy animals. 3.0T MR DWI was performed 7-10 days after RFA (mean, 8 days). Pathology exam was performed immediately after the completion of post- RFA MR imaging. Analyzing the features of MRI and ADC values in the pre- and post- RFA lesions of the VX2 tumors, and histopathologic results were compared with imaging findings.

RESULTS

The difference of ADC value between viable tumor and normal liver parenchyma was significant (P<.001). After RFA, when b = 200, 400, 600, 800, 1000 s/mm2, the differences of ADC values of viable tumor, granulation tissue, necrosis, normal liver parenchyma were significant (P<.001). At the time the animals were sacrificed after RFA and MR imaging, histopathologic results of local viable tumors were found in 9 (50%) of the 18 treated tumors. Macroscopic viable tumors were found at the RFA sites in 3 (17%), all 3 macroscopic viable tumors were visualized at the periphery of the RFA areas.

CONCLUSIONS

3.0T MR DWI can be used to follow up the progress of the RFA lesion, it is useful in detecting different tissues after RFA, and it is valuable in the further clinical research.

Percutaneous radiofrequency ablation of malignant liver tumors with ultrasound and CT fusion imaging guidance

BACKGROUND

To evaluate the feasibility, accuracy, and utility of sonography (US) and CT fusion imaging guidance for radiofrequency ablation (RFA) of malignant liver tumors not visualized on conventional US.

METHODS

Seventy-seven patients with hepatocellular carcinoma and 15 patients with metastatic liver cancer with a total of 136 lesions underwent RFA with US and CT fusion imaging guidance. The mean number of punctures, success rate of a single ablation session, local tumor progression rates, and long-term outcome were evaluated. Treatment efficacy was evaluated by dynamic CT and contrast-enhanced US 1 month after RFA.

RESULTS

RFA was technically feasible in all patients, and no major complications occurred. The mean ± SD time needed to synchronize US and CT images was 13.9 ± 11.9 minutes (range, 5-55 minutes). The success rate of a single ablation session was 83.8% (114/136), and tumor residue was present in 7.4% of lesions (10/136). The mean number of treatment sessions was 1.2 ± 0.5 sessions. During follow-up, local tumor progression was observed for 15 (11.9%) lesions. Distant tumor recurrence was found in 51 (55.4%) patients.

CONCLUSIONS

US and CT fusion-assisted RFA is a safe and efficacious treatment for patients with hepatocellular carcinoma and metastatic liver cancer.

Irreversible electroporation of hepatic malignancy

Hepatocellular carcinoma (HCC) is a worldwide problem of epidemic proportions, best treated in a multidisciplinary setting. Major advances have been made in all specialties that manage patients with HCC, with surgical options at one end of the spectrum and palliative chemotherapy on the other, and the vast majority of patients require the involvement and expertise of interventional oncology. Several ablative and transarterial technologies are currently available. Irreversible electroporation (IRE) is a new ablative technology that uses high-voltage, low-energy DC current to create nanopores in the cell membrane, disrupting the homeostasis mechanism and inducing cell death by initiating apoptosis. This article discusses the evolution of IRE as well as its safety and efficacy in the context of other ablative therapies in the treatment of hepatic malignancies.

Combining radiofrequency ablation and ethanol injection may achieve comparable long-term outcomes in larger hepatocellular carcinoma (3.1-4 cm) and in high-risk locations

Radiofrequency ablation (RFA) is more effective for hepatocellular carcinoma (HCC) < 3 cm. Combining percutaneous ethanol injection and RFA for HCC can increase ablation; however, the long-term outcome remains unknown. The aim of this study was to compare long-term outcomes between patients with HCC of 2-3 cm versus 3.1-4 cm and in high-risk versus non-high-risk locations after combination therapy. The primary endpoint was overall survival and the secondary endpoint was local tumor progression (LTP). Fifty-four consecutive patients with 72 tumors were enrolled. Twenty-two (30.6%) tumors and 60 (83.3%) tumors were of 3.1-4 cm and in high-risk locations, respectively. Primary technique effectiveness was comparable between HCC of 2-3 cm versus 3.1-4 cm (98% vs. 95.5%, p = 0.521), and HCC in non-high risk and high-risk locations (100% vs. 96.7%, p = 1.000). The cumulative survival rates at 1 year, 3 years, and 5 years were 90.3%, 78.9%, and 60.3%, respectively, in patients with HCC of 2-3 cm; 95.0%, 84.4%, and 69.3% in HCC of 3.1-4.0 cm (p = 0.397); 90.0%, 71.1%, and 71.1% in patients with HCC in non-high-risk locations; and 92.7%, 81.6%, and 65.4% in high-risk locations (p = 0.979). The cumulative LTP rates at 1 year, 3 years, and 5 years were 10.2%, 32.6%, and 32.6%, respectively, in all HCCs; 12.6%, 33.9%, and 33.9% in HCC of 2-3 cm; 4.8%, 29.5%, and 29.5% in HCC of 3.1-4 cm (p = 0.616); 16.7%, 50.0%, and 50.0% in patients with HCC in non-high-risk locations; and 8.8%, 29.9%, and 29.9% in patients with HCC in high-risk locations (p = 0.283). The cumulative survival and LTP rates were not significantly different among the various subgroups. Combining RFA and percutaneous ethanol injection achieved comparable long-term outcomes in HCCs of 2-3 cm versus 3.1-4.0 cm and in high-risk versus non-high-risk locations. A randomized controlled or cohort studies with larger sample size are warranted.

Increased serum autotaxin levels in hepatocellular carcinoma patients were caused by background liver fibrosis but not by carcinoma

BACKGROUND

Controversy exists as to whether autotaxin (ATX) may be importantly associated with pathophysiology of hepatocellular carcinoma (HCC).

METHODS

We evaluated serum ATX levels and its mRNA expression in consecutive 148 HCC patients treated with radiofrequency ablation (RFA) and 30 patients with hepatic resection.

RESULTS

Although increased serum ATX levels were observed in almost all the patients treated with RFA, they were not reduced after RFA. Furthermore, serum ATX levels were associated not with tumor burden but with the parameters predicting for liver fibrosis, such as liver stiffness values. Then, in surgically-treated patients, there was no significant correlation between serum ATX levels and ATX mRNA expression levels in HCC tissues. Notably, ATX mRNA expression levels in HCC tissues were not higher than those in peri-tumorous tissues. Finally, serum ATX levels in surgically-treated HCC patients were rather correlated with ATX mRNA expression levels in peri-tumorous tissues as well as with liver fibrosis stage.

CONCLUSION

The increase in serum ATX levels in HCC patients may not be caused by abundant ATX production in HCC tissues but by fibrosis in the background livers.

Risk factors for exceeding the Milan criteria after successful radiofrequency ablation in patients with early-stage hepatocellular carcinoma

Radiofrequency ablation (RFA) is an effective and safe noninvasive treatment for hepatocellular carcinoma (HCC) and may be useful as a bridging therapy in liver transplantation. The prognosis after liver transplantation for patients within the Milan criteria is excellent. This study was aimed at identifying risk factors associated with exceeding the Milan criteria after initial locally curative RFA therapy. Among 554 primary HCC patients, 323 with early-stage HCC after RFA were analyzed (mean age = 66 years). Two hundred forty-eight patients had hepatitis C virus, 33 patients had hepatitis B virus, and 41 patients had neither hepatitis B nor hepatitis C; 256, 67, and 0 patients were classified as Child-Pugh A, B, and C, respectively. The rates of cumulative overall survival and recurrence exceeding the Milan criteria were analyzed with Kaplan-Meier analysis, and factors associated with overall survival were determined with Cox proportional hazards analysis. The cumulative overall survival rates at 1, 3, 5, and 10 years were 96.2%, 84.4%, 69.9%, and 40.6% respectively, without liver transplantation. The cumulative rates of recurrence exceeding the Milan criteria at 1, 3, and 5 years were 15.1%, 46.0%, and 61.1% respectively. An alpha-fetoprotein (AFP) level > 100 ng/mL and recurrence within 1 year after initial ablation were independently associated with earlier recurrence exceeding the Milan criteria and overall survival. The 3- and 5-year survival rates for patients with both risk factors were 33.5% and 22.6%, respectively, despite an early stage at initial ablation. In conclusion, a higher AFP level and HCC recurrence within 1 year of RFA are risk factors for exceeding the Milan criteria and for overall survival. Early liver transplantation or adjuvant therapy should be considered for patients with both risk factors.

Percutaneous microwave ablation for hepatocellular carcinoma adjacent to large vessels: a long-term follow-up

PURPOSE

To retrospectively evaluate the effectiveness and safety of ultrasound (US)-guided percutaneous microwave ablation (MWA) in the treatment of hepatocellular carcinoma (HCC) adjacent to large vessels.

MATERIALS AND METHODS

From February 2006 to February 2013, 452 patients with 605 HCC nodules were treated with US-guided percutaneous MWA. Into large vessels group (Group L), 139 patients with 163 lesions (diameter, 1.0-7.0 cm; mean, 2.5±1.1 cm) located less than 5mm away from large vessels were enrolled. And 313 patients with 442 lesions (diameter, 1.0-8.0 cm; mean, 2.5±1.2 cm) located more than 5mm away from hepatic surface, large vessels, gallbladder and gastrointestinal tract were included in control group (Group C). During the ablation, the temperature of marginal ablation tissues was monitored and controlled.

RESULTS

The median follow-up time was 24.5 months (range 2.1-87.7 months) in Group L, and 25.7 months (range 1.6-93.9 months) in Group C. Technical effectiveness was achieved in 157 of 163 (96.3%) tumors in Group L and 429 of 442 (97.1%) tumors in Group C, respectively (p>0.05). The 1-, 3- and 5-year local tumor progression rates and the 1-, 3- and 5-year accumulative survival rates in the two groups have no significantly statistical differences. In addition, no immediate or periprocedural major complications, no delayed complication of vessels or bile ducts injury were found in both of the two groups.

CONCLUSIONS

With strict temperature monitoring, US-guided percutaneous MWA is an efficient and safe technology in treating hepatocellular carcinoma adjacent to large vessels.

Post-operative pericardial effusion following treatment of small hepatocellular carcinoma with radiofrequency ablation: A case report

Radiofrequency ablation (RFA) is a minimally invasive technique used to treat liver tumors. The current study presents the case of a patient with hepatocellular carcinoma who suffered from post-operative pericardial effusion following RFA treatment. We hypothesize that RFA thermal conduction may damage the diaphragm and pericardium, leading to local edema in the pericardium. RFA is a minimally invasive technique, however, adequate preparatory work must be performed prior to surgery, including a comprehensive assessment of the patient. During surgery, the location and extent of the region to receive RFA must be determined precisely in order to reduce the range of damage and to avoid post-operative complications. This study describes a case of pericardial effusion caused by RFA of liver cancer. We analyzed the causes and preventive measures for pericardial effusion in order to contribute to the prevention pericardial effusion that is complicated by RFA of liver cancer.

Perivascular versus nonperivascular small HCC treated with percutaneous RF ablation: retrospective comparison of long-term therapeutic outcomes

PURPOSE

To compare the long-term therapeutic outcomes of radiofrequency (RF) ablation for small perivascular hepatocellular carcinoma (HCC) and nonperivascular HCC.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board. Between December 2004 and April 2008, 241 patients (175 men and 66 women; age range, 32-82 years) with a single early-stage HCC that was 3 cm or smaller in the greatest dimension underwent ultrasonography-guided percutaneous RF ablation as a first-line treatment. The patients were divided into two groups according to the presence or absence of contacting hepatic vessels that were 3 mm or larger in axial diameter: a group with perivascular HCC (n = 58) and a group with nonperivascular HCC (n = 183). Cumulative local tumor progression, disease-free and long-term survival rates, and prognostic factors were assessed by using Cox proportional hazard models with Bonferroni correction.

RESULTS

The overall median follow-up period was 58 months (range, 13-92 months). The cumulative local tumor progression rates were 10%, 16%, and 26% at 1, 3, and 5 years, respectively, in the perivascular group, and 6.7%, 15.5%, and 20.5% in the nonperivascular group; the differences were not significant (P = .323). The corresponding disease-free survival rates were 79%, 41%, and 29% in the perivascular group and 71.3%, 38.7%, and 26.0% in the nonperivascular group, with no significant difference (P = .689). The corresponding overall survival rates were 100%, 94%, and 82% in the perivascular group and 100%, 88.4%, and 73.9% in the nonperivascular group, also without significant difference (P = .267). There was no significant prognostic factor for local tumor progression, whereas extrahepatic and intrahepatic distant recurrences were significant prognostic factors for overall survival in multivariable analysis.

CONCLUSION

The long-term therapeutic outcomes of RF ablation as first-line treatment for small perivascular HCC were similar to those for nonperivascular HCC.

Diaphragmatic perforation with colonic herniation due to hepatic radiofrequency ablation: A case report and review of the literature

Radiofrequency ablation (RFA) has been widely accepted as an alternative treatment for unresectable primary and metastatic hepatic tumors, with satisfactory rates of local response and significant improvements in rates of overall survival. Numerous large series studies have shown that RFA is safe and effective, with a low mortality rate and a low major complication rate. Major complications, including diaphragmatic perforation and hernia, have rarely been previously reported. The current case report presents a case of diaphragmatic hernia with perforation of the incarcerated colon in the thoracic cavity 12 months following hepatic RFA, and reviews nine previously reported cases of diaphragmatic hernia. Comprehensive analysis of the nine cases demonstrated possibilities leading to diaphragmatic hernia following diaphragmatic thermal injury as a consequence of hepatic RFA. Clinicians and radiologists must consider diaphragmatic thermal damage following hepatic RFA for liver tumors adjacent to the diaphragm, particularly for patients with symptoms of ileus, dyspnea, chest pain, pleural effusion and right shoulder pain.

A novel needle guide system to perform percutaneous laser ablation of liver tumors using the multifiber technique

BACKGROUND

Previous studies have shown that laser ablation with the multifiber technique is effective in the treatment of liver tumors. However, the correct positioning of multiple needles may be challenging.

PURPOSE

To investigate the use of a novel needle guide system that was developed to perform percutaneous laser ablation of liver tumors with the multifiber technique under ultrasonographic guidance.

MATERIAL AND METHODS

Between February 2009 and June 2011, 116 patients (104 hepatocellular carcinomas and 12 metastases) with 127 liver nodules (median diameter, 3.0 cm; range, 1.5-6.0) were treated. Nineteen nodules were in high-risk locations. A needle guide with separate channels to insert two needles in a parallel position and at a prefixed distance was used.

RESULTS

Needles were positioned inside the target nodule easily and quickly, and correct spacing (1.5-1.8 cm) between light sources was immediately achieved. Complete tumor ablation was achieved in a single session in 112 (88.2%) lesions. In nodules ≤3.0 cm and >3.0 cm in size, ablation was complete in 93.6% and 79.6% of cases, respectively. Of note, complete ablation was achieved in 91.7% of nodules up to 5.0 cm.

CONCLUSION

With the new guidance system, needles could be inserted in parallel fashion, which facilitated positioning the needles in geometrical configurations to maximize the ablative effect. Worthy of note, the complete ablation rate in nodules >3.0 cm using the new guide system was higher than what has been reported in the literature so far.

Surgical resection versus open-approach radiofrequency ablation for small hepatocellular carcinomas within Milan criteria after successful transcatheter arterial chemoembolization

AIMS

The aim of this study was to compare the effectiveness and safety of hepatic resection versus open-approach RFA (ORFA) for small hepatocellular carcinomas (HCC) within Milan criteria after successful downstaging therapy by transcatheter arterial chemoembolization.

MATERIAL AND METHODS

Between February 2005 and February 2008, a total of 110 patients with advanced HCC met the Milan criteria after successful downstaging therapy; 58 patients then underwent hepatic resection and 52 received ORFA. Outcomes, including short- and long-term morbidity, 1-, 3-, and 5-year mortality and HCC-free survival, were analyzed and compared between the two groups.

RESULTS

Patients in the hepatic resection and ORFA groups showed similar baseline characteristics and downstaging protocols. The ORFA group showed less blood loss, lower hospital costs, shorter surgical time, and fewer hospital stay days (P < 0.05). The 1-, 3-, and 5-year overall survival rates were 94.8, 86.2, and 79.3%, respectively, with liver resection and 96.2, 82.7, and 76.9% with ORFA (P=0.772). The 1-, 3-, and 5-year recurrence-free survival rates were 93.1, 81.0, and 77.6% with resection and 94.2, 76.9, and 73.1% with ORFA (P=0.705). The ORFA patients suffered fewer postoperative complications (P=0.09), particularly among the cases of central HCC (P=0.015).

CONCLUSION

Resection and ORFA achieved similar survival benefits in the management of HCC within Milan criteria after successful downstaging. The decreased blood loss, hospital costs, surgical time, and hospital stay days, and lower complication rates in central cases render ORFA a preferred treatment option.

First-line radiofrequency ablation with or without artificial ascites for hepatocellular carcinomas in a subcapsular location: local control rate and risk of peritoneal seeding at long-term follow-up

AIM

To compare the long-term local control of hepatocellular carcinoma (HCC) and risk of peritoneal seeding via percutaneous radiofrequency ablation (RFA) using artificial ascites with those of RFA without artificial ascites.

MATERIALS AND METHODS

The Institutional Review Board approved this retrospective study. From April 2005 to February 2008, 160 patients (121 men, 39 women; age range 36-79 years) with a single subcapsular HCC (mean size 2.19 cm) were treated with ultrasonography-guided percutaneous RFA as a first-line therapy. Forty-four patients were treated with RFA using artificial ascites, whereas the other 116 patients were treated without artificial ascites. The cumulative local tumour progression (LTP) and peritoneal seeding were compared in both groups using follow-up computed tomography (CT). Cumulative LTP rates were analysed using the Kaplan-Meier method and the log-rank test. Risk of peritoneal seeding was investigated by means of multivariate analysis.

RESULTS

The overall median follow-up period was 52.5 months (range 13-76 months). The 1, 2, 4, and 6 year cumulative LTP rates were 17.1, 27.6, 35.2, and 35.2%, respectively, in the group with artificial ascites, and 8, 15.2, 26.6, and 34.4% in the group without artificial ascites, without significant difference (p = 0.332). The rates of peritoneal seeding were 6.8% (3/44) in the group with artificial ascites and 2.6% (3/116) in the group without artificial ascites, a non-significant difference (p = 0.347). The biopsy prior to RFA was the independent risk factor of peritoneal seeding regardless of the use of artificial ascites.

CONCLUSION

Long-term local tumour control and risk of peritoneal seeding were comparable for RFA with or without artificial ascites when used as a first-line therapy for subcapsular HCC.

Endoscopic versus open radiofrequency ablation for treatment of small hepatocellular carcinoma

BACKGROUND

Surgical radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) is associated with superior oncological outcome in comparison with percutaneous RFA. The present study aimed to retrospectively evaluate the relative perioperative safety and postoperative outcome of the laparoscopic or thoracoscopic approach versus the open approach to RFA for small HCC.

METHODS

A retrospective analysis was performed in 55 consecutive patients who underwent open (n = 32) or laparoscopic/thoracoscopic (LTS) RFA (n = 23) for primary unresectable HCC between January 2005 and December 2010. Baseline characteristics, survival/recurrence rates, and complications after treatment were compared between the two groups.

RESULTS

There was a trend showing that LTS RFA was performed for tumors located in the anterior segment (e.g., segments III, V, VIII). The LTS RFA group had a significantly lower intraoperative blood loss, shorter operative time, and shorter postoperative hospital stay, compared with the open RFA group. No major postoperative complications occurred in patients who underwent LTS RFA. No significant differences in overall survival, recurrence-free survival and local recurrence rates were observed between the two groups.

CONCLUSIONS

In consideration of operative invasiveness and postoperative recovery, LTS RFA is superior to the open approach in patients with small HCC. Moreover, the surgical outcome did not differ between the two approaches. Laparoscopic/thorascopic RFA can be considered to be a useful procedure for ablation therapy.

Management of hepatocellular carcinoma: Enlightening the gray zones

Management of hepatocellular carcinoma (HCC) has been continuously evolving during recent years. HCC is a worldwide clinical and social issue and typically a complicates cirrhosis. The incidence of HCC is increasing, not only in the general population of patients with cirrhosis, but particularly in some subgroups of patients, like those with human immunodeficiency virus infection or thalassemia. Since a 3% annual HCC incidence has been estimated in cirrhosis, a bi-annual screening is generally suggested. The diagnostic criteria of HCC has recently had a dramatic evolution during recent years. HCC diagnosis is now made only on radiological criteria in the majority of the cases. In the context of cirrhosis, the universally accepted criteria for HCC diagnosis is contrast enhancement in arterial phase and washout in venous/late phase at imaging, the so called “typical pattern”. However, recently updated guidelines slightly differ in diagnostic criteria. Apart from liver transplantation, the only cure of both HCC and underlying liver cirrhosis, all the other treatments have to match with higher rate of HCC recurrence. The latter can be classified into curative (resection and percutaneous ablation) and palliative treatments. The aim of this paper was to review the current knowledge on management of HCC and to enlighten the areas of uncertainty.

Frequency, risk factors and survival associated with an intrasubsegmental recurrence after radiofrequency ablation for hepatocellular carcinoma

BACKGROUND

In the treatment of hepatocellular carcinoma (HCC), hepatic resection has the advantage over radiofrequency ablation (RFA) in terms of systematic removal of a hepatic segment.

METHODS

We enrolled 303 consecutive patients of a single naïve HCC that had been treated by RFA at The University of Tokyo Hospital from 1999 to 2004. Recurrence was categorized as either intra- or extra-subsegmental as according to the Couinaud's segment of the original nodule. To assess the relationship between the subsegments of the original and recurrent nodules, we calculated the kappa coefficient. We assessed the risk factors for intra- and extra-subsegmental recurrence independently using univariate and multivariate Cox proportional hazard regression. We also assessed the impact of the mode of recurrence on the survival outcome.

RESULTS

During the follow-up period, 201 patients in our cohort showed tumor recurrence distributed in a total of 340 subsegments. Recurrence was categorized as exclusively intra-subsegmental, exclusively extra-subsegmental, and simultaneously intra- and extra-subsegmental in 40 (20%), 110 (55%), and 51 (25%) patients, respectively. The kappa coefficient was measured at 0.135 (95% CI, 0.079-0.190; P<0.001). Multivariate analysis revealed that of the tumor size, AFP value and platelet count were all risk factors for both intra- and extra-subsegmental recurrence. Of the patients in whom recurrent HCC was found to be exclusively intra-subsegmental, extra-subsegmental, and simultaneously intra- and extra-subsegmental, 37 (92.5%), 99 (90.8%) and 42 (82.3%), respectively, were treated using RFA. The survival outcomes after recurrence were similar between patients with an exclusively intra- or extra-subsegmental recurrence.

CONCLUSIONS

The effectiveness of systematic subsegmentectomy may be limited in the patients with both HCC and chronic liver disease who frequently undergo multi-focal tumor recurrence.

Computed tomography follow-up for the detection of hepatocellular carcinoma recurrence after initial radiofrequency ablation: a single-center experience

PURPOSE

Recurrence of hepatocellular carcinoma (HCC) is very common even after curative resection or ablation. This retrospective study compared the radiologic features of recurrent HCC seen by computed tomography (CT) to evaluate our empirical protocol of CT surveillance using 4-month intervals.

MATERIALS AND METHODS

A total of 113 patients who were diagnosed with a first HCC recurrence after radiofrequency (RF) ablation between January 2005 and December 2006 were enrolled at a single center. Definite HCC was defined as hyperattenuation in the arterial phase with washout in the portal venous phase, and a diagnosis of naive and recurrent HCC was based on dynamic CT findings. Recurrent nodules were classified according to the enhancement patterns of previous CT images. The treatment modality for recurrent HCC and survival were evaluated.

RESULTS

One hundred seventy-seven nodules were diagnosed as recurrent HCC: 31 (17.5%) had already been diagnosed on previous CT images as typical HCC, 72 (40.6%) had arterial hypervascularity without washout in the portal venous phase, 21 (11.9%) showed portal venous phase washout without arterial hypervascularity, and no lesions were noted in the remaining 49 (27.7%). Tumor size at recurrence was smaller than 2 cm in diameter in 98 (86.7%) cases. One hundred four patients were treated for recurrent HCC with RF ablation. The 5-year survival rate after recurrence was 49.8%. There was no significant difference in survival among groups divided by the enhancement pattern on the previous CT examination.

CONCLUSIONS

Dynamic CT in 4-month intervals is an acceptable recurrence-monitoring strategy because it detects most recurrent nodules at a stage at which RF ablation is still feasible.

Local ablation for hepatocellular carcinoma in taiwan

Hepatocellular carcinoma (HCC) is the second commonest cancer in Taiwan. The national surveillance program can detect HCC in its early stages, and various curative modalities (including surgical resection, orthotopic liver transplantation, and local ablation) are employed for the treatment of small HCC. Local ablation therapies are currently advocated for early-stage HCC that is unresectable because of co-morbidities, the need to preserve liver function, or refusal of resection. Among the various local ablation therapies, the most commonly used modalities include percutaneous ethanol injection and radiofrequency ablation (RFA); percutaneous acetic acid injection and microwave ablation are used less often. RFA is more commonly employed than other local ablative modalities in Taiwan because the technique is highly effective, minimally invasive, and requires fewer sessions. RFA is therefore advocated in Taiwan as the first-line curative therapy for unresectable HCC or even for resectable HCC. However, current RFA procedures are less effective against tumors that are in high-risk or difficult-to-ablate locations, are poorly visualized on ultrasonography (US), or are large. Recent advancements in RFA in Taiwan can resolve these issues by the creation of artificial ascites or pleural effusion, application of real-time virtual US assistance, use of combination therapy before RFA, or use of switching RF controllers with multiple electrodes. This review article provides updates on the clinical outcomes and advances in local ablative modalities (mostly RFA) for HCC in Taiwan.

Therapeutic efficacy and safety of percutaneous ethanol injection with or without combined radiofrequency ablation for hepatocellular carcinomas in high risk locations

OBJECTIVE

To evaluate the therapeutic efficacy and safety of percutaneous ethanol injection (PEI) alone and combined with radiofrequency ablation (RFA) for hepatocellular carcinomas (HCCs) in high risk locations.

MATERIALS AND METHODS

We performed PEI for HCCs in RFA-high risk locations, either alone or in combination with RFA. There were 20 HCCs (1.7 ± 0.9 cm) in 20 patients (PEI group: n = 12; PEI + RFA group: n = 8). We evaluated technical success, local tumor progression and complications in both groups.

RESULTS

Technical success was achieved in all HCCs in both groups. During follow-up, local tumor progression was found in 41.7% (5/12) in the PEI group, whereas 12.5% (1/8) for the PEI + RFA group (p = 0.32). Bile duct dilatation was the most common complication, especially when the tumors were in periportal locations; 55% (5/9) in the PEI group and 50% (2/4) in the PEI + RFA group (p = 1.00). One patient in the PEI group developed severe biliary stricture and upstream dilatation that resulted in atrophy of the left hepatic lobe. One patient treated with PEI + RFA developed cholangitis and an abscess.

CONCLUSION

Combined PEI and RFA treatment has a tendency to be more effective than PEI alone for managing HCCs in high risk locations, although the difference is not statistically significant. Even though PEI is generally accepted as a safe procedure, it may cause major biliary complications for managing HCCs adjacent to the portal vein.

Usefulness of contrast-enhanced ultrasonography to evaluate the post-treatment responses of radiofrequency ablation for hepatocellular carcinoma: comparison with dynamic CT

OBJECTIVE

Contrast-enhanced ultrasonography (CEUS) with Sonazoid® and dynamic computed tomography (CT) were used to evaluate radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). Local recurrence rate was used as the gold standard of evaluation.

METHODS

From January 2007 to December 2011, 86 HCCs from 70 patients were treated with RFA. CEUS with Sonazoid and dynamic CT were then used to evaluate the effect of RFA. For CEUS and dynamic CT, effects were classified as follows: (1) complete ablated response with safety margin >5 mm (CRSM+); (2) complete ablated response but with safety margin <5 mm (CRSM-); (3) incomplete, residual tumor detected after treatment.

RESULTS

CEUS judged 33 cases as CRSM+, while dynamic CT identified 49 cases. None of these 33 cases from the CEUS group had local recurrences, while dynamic CT had 1 case. CEUS judged 49 cases as CRSM-, compared to 34 cases with dynamic CT. Of these, 9 cases of CEUS and 8 cases of dynamic CT showed local recurrences. Two cases diagnosed as 'incomplete' by CEUS and dynamic CT had recurrences within 1 year.

CONCLUSION

CEUS can be used to assess the efficacy of RFA for HCC, with the potential to reduce the number of CT scans required for confirmation.

Effectiveness, safety, and local progression after percutaneous laser ablation for hepatocellular carcinoma nodules up to 4 cm are not affected by tumor location

OBJECTIVE

A high-risk location--defined as the tumor margin being less than 5 mm from large vessels or vital structures--represents a well-known limitation and contraindication for radiofrequency ablation of hepatocellular carcinoma (HCC) nodules. The aim of this study was to verify whether HCC nodule location negatively affected the outcome of percutaneous laser ablation in terms of its primary effectiveness, safety, and ability to prevent local tumor progression.

MATERIALS AND METHODS

The medical records and radiologic examinations of 164 cirrhotic patients (90 men, 74 women; mean age ± SD, 68.6 ± 8.3 years) with 182 HCC nodules 4 cm or smaller (mean diameter ± SD, 2.7 ± 0.78 cm) that had been treated by laser ablation between 1996 and 2008 were retrospectively analyzed. One hundred six patients had 116 nodules in high-risk sites (high-risk group), whereas 58 patients had 66 tumors located elsewhere (standard-risk group).

RESULTS

The overall median follow-up was 81 months (range, 6-144 months). The initial complete ablation rate per nodule did not significantly differ between the high-risk group and the standard-risk group (92.2% vs 95.5%, respectively; p = 0.2711). Rates of major complications (high-risk group vs standard-risk group, 1.9% [including one death] vs 0%) and minor complications (5.6% vs 1.0%) were not statistically different between the two groups. Only side effects were recorded significantly more often in high-risk patients than in standard-risk patients (31.5% vs 19.8%; p = 0.049). There was no significant difference in either cumulative incidence of local tumor progression (p = 0.499) or local tumor progression-free survival (p = 0.499, log rank test) between the high-risk group and the standard-risk group.

CONCLUSION

When laser ablation is used to treat small HCC nodules, tumor location does not have a significant negative impact on the technique's primary effectiveness or safety or on its ability to achieve local control of disease.

Irreversible electroporation for unresectable hepatocellular carcinoma: initial experience and review of safety and outcomes

The aims of this study were to evaluate the safety, feasibility and tumour response of _irreversible electroporation, a non-thermal ablation technique, for the treatment of unresectable hepatocellular carcinoma. The endpoints were safety and local treatment efficacy. Patients with unresectable tumours and tumours not amenable for radiofrequency _ablation because of their vicinity to organs vulnerable to thermal damage such as the bowel or because they were close to large blood vessels that would limit efficacy of ablation due to the heat sink effect were treated with irreversible electroporation using percutaneous _ultrasound and/or computed tomography guided electrode placement between November 2008 and _December 2009. Early, late, minor and major complications were recorded. Tumour response was determined on triphasic helical computed tomography follow-up at one month, then every three months post-procedure. Eleven patients received IRE therapy to 18 HCC lesions (Mean diameter 2.44 ± 0.99 cm; range 1.0-6.1 cm) with five patients having more than one treated HCC. Mean follow-up was 18 months (range 14-24 months). Six patients required repeat treatments for local residual or recurrent disease; two of these also had IRE for distant intrahepatic recurrence. No serious complications were observed despite seven lesions lying adjacent to important structures or organs. Four patients developed transient urinary retention and seven developed transient local post-procedure pain. After IRE therapy, 13 (72%) lesions were completely ablated with 93% success for lesions ≤ 3 cm (13/14). The local recurrence-free period was 18 ± 4 months and the distance recurrence free period was 14 ± 6 months. These preliminary results suggest that IRE is a safe and feasible technique for local ablation of HCC, particularly for lesions less than 3 cm. No major complications were encountered during this study even for tumours close to essential structures or organs.

History, ethics, advantages and limitations of experimental models for hepatic ablation

Numerous techniques developed in medicine require careful evaluation to determine their indications, limitations and potential side effects prior to their clinical use. At present this generally involves the use of animal models which is undesirable from an ethical standpoint, requires complex and time-consuming authorization, and is very expensive. This process is exemplified in the development of hepatic ablation techniques, starting experiments on explanted livers and progressing to safety and efficacy studies in living animals prior to clinical studies. The two main approaches used are ex vivo isolated non-perfused liver models and in vivo animal models. Ex vivo non perfused models are less expensive, easier to obtain but not suitable to study the heat sink effect or experiments requiring several hours. In vivo animal models closely resemble clinical subjects but often are expensive and have small sample sizes due to ethical guidelines. Isolated perfused ex vivo liver models have been used to study drug toxicity, liver failure, organ transplantation and hepatic ablation and combine advantages of both previous models.

Image-guided ablation for hepatocellular carcinoma

Image-guided ablation is accepted as the best therapeutic choice for patients with early-stage hepatocellular carcinoma (HCC) when surgical options-including resection and transplantation-are precluded. The term image-guided tumor ablation is defined as the direct application of chemical substances or sources of energy to a focal tumor in an attempt to achieve eradication or substantial tumor destruction. Over the past 25 years, several methods for local tumor destruction have been developed and clinically tested. Radiofrequency ablation (RFA) has shown superior anticancer effect and greater survival benefit with respect to the seminal percutaneous technique, ethanol injection, in meta-analyses of randomized controlled trials, and is currently established as the standard ablative modality. Nevertheless, novel thermal and nonthermal techniques for tumor ablation-including microwave ablation and irreversible electroporation-seem to have potential to improve the efficacy of RFA and are currently undergoing clinical investigation.

Percutaneous ethanol injection for hepatocellular carcinoma: 20-year outcome and prognostic factors

BACKGROUND

Ethanol injection is the best-known image-guided percutaneous ablation for hepatocellular carcinoma (HCC) and a well-tolerated, inexpensive procedure with few adverse effects. However, there have been few reports on its long-term results.

AIMS

We report a 20-year consecutive case series at a tertiary referral centre.

METHODS

We performed 2147 ethanol injection treatments on 685 primary HCC patients and analysed a collected database.

RESULTS

Final computed tomography demonstrated complete ablation of treated tumours in 2108 (98.2%) of the 2147 treatments. With a median follow-up of 51.6 months, 5-, 10- and 20-year survival rates were 49.0% [95% confidence interval (CI) = 45.3-53.0%], 17.9% (95% CI = 15.0-21.2%) and 7.2% (95% CI = 4..5-11.5%) respectively. Multivariate analysis demonstrated that age, Child-Pugh class, tumour size, tumour number and serum alpha-fetoprotein level were significant prognostic factors for survival. Five-, 10- and 20-year local tumour progression rates were 18.2% (95% CI = 15.0-21.4%), 18.4% (95% CI = 15.2-21.6%) and 18.4% (95% CI = 15.2-21.6%) respectively. Five-, 10- and 20-year distant recurrence rates were 53.5% (95% CI = 49.4-57.7%), 60.4 (95% CI = 56.3-64.5%) and 60.8% (95% CI = 56.7-64.9%) respectively. There were 45 complications (2.1%) and two deaths (0.09%).

CONCLUSIONS

Ethanol injection was potentially curative for HCC, resulting in survival for more than 20 years. This study suggests that new ablation therapies will achieve similar or even better long-term results in HCC.

Gallbladder Needle Decompression during Radiofrequency Ablation of an Adjacent Liver Tumour

Gallbladder perforation with bile leak can result from thermal injury during radiofrequency ablation of liver tumours. Two case studies demonstrate a technique for preventing gallbladder injury to the peritoneal surface of a distended gallbladder adjacent to the anticipated hepatic ablation zone. The use of percutaneous gallbladder needle decompression can safely separate or retract the peritoneal surface of the gallbladder from a contiguous hepatic radiofrequency ablation zone.

Pain analysis in patients with hepatocellular carcinoma: irreversible electroporation versus radiofrequency ablation-initial observations

PURPOSE

To retrospectively compare the postprocedure pain of hepatocellular carcinoma treated with irreversible electroporation (IRE) with radiofrequency ablation (RFA).

METHODS

This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved study compared postprocedure pain in 21 patients (15 men, six women; mean age 61.5 years) who underwent IRE of 29 intrahepatic lesions (mean size 2.20 cm) in 28 IRE sessions with 22 patients (16 men, six women; mean age 60.2 years) who underwent RFA of 27 lesions (mean size 3.38 cm) in 25 RFA sessions. Pain was determined by patient-disclosed scores with an 11-point numerical rating scale and 24 h cumulative hydromorphone use from patient-controlled analgesia pump. Complications were noted. Statistical significance was evaluated by Fisher's exact test, the Chi-square test, and Student's t test.

RESULTS

There was no significant difference in the cumulative hydromorphone dose (1.54 mg (IRE) vs. 1.24 mg (RFA); P = 0.52) and in the mean pain score (1.96 (IRE) vs. 2.25 (RFA); P = 0.70). In nine (32.14 %) of 28 IRE sessions and 11 (44.0 %) of 25 RFA sessions, patients reported no pain. Complications occurred in three (10.7 %) of 28 IRE treatments and included pneumothorax (n = 1), pleural effusion (n = 1), and bleeding in the form of hemothorax (n = 1); one (4 %) of 25 RFA treatments included burn.

CONCLUSION

IRE is comparable to RFA in the amount of pain that patients experience and the amount of pain medication self-administered. Both modalities were well tolerated by patients. Prospective, randomized trials are necessary to further evaluate these findings.

Limitation of repeated radiofrequency ablation in hepatocellular carcinoma: proposal of a three (times) × 3 (years) index

BACKGROUND AND AIM

Percutaneous radiofrequency ablation (RFA) has been shown to be a highly effective treatment for hepatocellular carcinoma (HCC). We investigated the controllability of HCC and explored the algorithm of therapeutic strategy for HCC in patients who met the RFA criteria.

METHODS

We enrolled 472 patients with HCC who met the RFA criteria (≤ 3 nodules, ≤ 3 cm) and underwent RFA for initial therapy. Patients who underwent repeated RFA were evaluated retrospectively when HCC exceeded the RFA criteria, or the functional hepatic reserve progressed to Child-Pugh grade C.

RESULTS

Overall survival rates were: 1 year, 96%; 3 years, 79%; and 5 years, 56%. In 5 years, 14% of patients progressed to Child-Pugh grade C. Meanwhile, 47% of patients exceeded the RFA criteria. Annually, 8% of patients deviated from the RFA criteria. The percentage of patients who were able to receive RFA significantly decreased at the fourth session compared with up to the third session. The survival rates decreased at the rate of 7% annually until the third year after the initial RFA. Afterwards, it shifted to a decrease at the rate of 12% annually. In a multivariate analysis, the presence of hepatitis C virus infection and the existence of a single tumor were identified as significant independent factors contributing to probabilities exceeding the RFA criteria.

CONCLUSIONS

HCC was controlled by RFA up to three RFA treatments and 3 years from the initial therapy. On this basis, we propose a "three (times) × 3 (years) index" for considering a shift from RFA to other treatment modalities.

Influence of ablative margin on local tumor progression and survival in patients with HCC ≤4 cm after laser ablation

BACKGROUND

Ablation of the normal hepatic parenchyma surrounding the tumor (ablative margin [AM]) is necessary to prevent local tumor progression.

PURPOSE

To assess the prognostic value of the ablative margin in patients with HCC ≤4 cm treated with US-guided laser ablation.

MATERIAL AND METHODS

A cohort of 116 patients (53 women and 63 men, age range 42-82 years) with 132 HCC nodules ≤4 cm completely ablated by US-guided laser ablation was retrospectively analyzed. Rates of local tumor progression were compared using different ablative margin cut-offs (≥2.5, 5.0, 7.5, and 10.0 mm). Survival probability curves were obtained with the Kaplan-Meier method.

RESULTS

The mean period of follow-up was 42 months (range 3-114 months). Local tumor progression was identified in 24 out of 132 lesions (18%), with an average time to progression of 24 months (range 6-36 months). A significant difference in local tumor progression was observed only if the ablative margin was ≥7.5 mm (7% vs. 23%, P = 0.020). Survival curves of patients with or without an ablative margin ≥7.5 mm were not different (P = 0.665; mean survival time 43.8 ± 3.1 and 46.8 ± 6.1 for an AM < or ≥7.5 mm, respectively).

CONCLUSION

An ablative margin ≥7.5 mm turned out to be useful in preventing local tumor progression but did not affect long-term survival in patients with HCC ≤4 cm treated with laser ablation.

Radiofrequency ablation for hepatocellular carcinoma: 10-year outcome and prognostic factors

OBJECTIVES

Radiofrequency ablation (RFA) is widely performed for hepatocellular carcinoma (HCC). However, there has been no report on 10-year outcome of RFA. The objective of this study was to report a 10-year consecutive case series at a tertiary referral center.

METHODS

We performed 2,982 RFA treatments on 1,170 primary HCC patients and analyzed a collected database.

RESULTS

Final computed tomography images showed complete tumor ablation in 2,964 (99.4%) of 2,982 treatments performed for the 1,170 primary HCC patients. With a median follow-up of 38.2 months, 5- and 10-year survival rates were 60.2% (95% confidence interval (CI): 56.7-63.9%) and 27.3% (95% CI: 21.5-34.7%), respectively. Multivariate analysis demonstrated that age, antibody to hepatitis C virus (anti-HCV), Child-Pugh class, tumor size, tumor number, serum des-γ-carboxy-prothrombin (DCP) level, and serum lectin-reactive α-fetoprotein level (AFP-L3) were significantly related to survival. Five- and 10-year local tumor progression rates were both 3.2% (95% CI: 2.1-4.3%). Serum DCP level alone was significantly related to local tumor progression. Five- and 10-year distant recurrence rates were 74.8% (95% CI: 71.8-77.8%) and 80.8% (95% CI: 77.4-84.3%), respectively. Anti-HCV, Child-Pugh class, platelet count, tumor size, tumor number, serum AFP level, and serum DCP level were significantly related to distant recurrence. There were 67 complications (2.2%) and 1 death (0.03%).

CONCLUSIONS

RFA could be locally curative for HCC, resulting in survival for as long as 10 years, and was a safe procedure. RFA might be a first-line treatment for selected patients with early-stage HCC.

Local-regional treatment of hepatocellular carcinoma

Local-regional treatments play a key role in the management of hepatocellular carcinoma (HCC). Image-guided tumor ablation is recommended in patients with early-stage HCC when surgical options are precluded and can replace resection in selected patients. Radiofrequency (RF) ablation has shown superior anticancer effects and greater survival benefit with respect to the seminal percutaneous technique, ethanol injection, in meta-analyses of randomized controlled trials and is currently established as the standard method for local tumor treatment. Novel thermal and nonthermal techniques for tumor ablation, including microwave ablation and irreversible electroporation, seem to have potential to overcome the limitations of RF ablation and warrant further clinical investigation. Transcatheter arterial chemoembolization (TACE) is the standard of care for patients with asymptomatic noninvasive multinodular tumors in intermediate-stage disease. Embolic microspheres that have the ability to release a drug in a controlled and sustained fashion have been shown to substantially increase the safety and efficacy of TACE in comparison to conventional ethiodized oil-based regimens. The available data for radioembolization with yttrium 90 suggest that this is a potential new option for patients with HCC, and future studies should be devoted to assessments of the role of radioembolization in the treatment algorithm for HCC.

Percutaneous radiofrequency ablation for malignant liver tumours in challenging locations

PURPOSE

To evaluate the treatment results of radiofrequency ablation (RFA) for primary and metastatic malignant liver tumours in challenging locations and also to present the treatment strategy that was used in these cases.

PATIENTS AND METHODS

From January 2007 to January 2010, we performed CT-guided RFA on 528 lesions in 402 patients (265 men and 137 women; mean age 65.1 years, range 19-82 years) with liver tumours (primary and metastatic) of which 98 lesions in 84 patients (55 men and 29 women; mean age 67.8 years, range 33-82 years) were located in challenging locations, defined as less than 5 mm from a large vessel or an extrahepatic organ (heart, lung, gall bladder, right kidney or gastrointestinal tract). The sizes of the tumours ranged 1.5-6 cm. We used two different RFA systems with an expandable needle electrode (RITA; Rita Medical Systems, Inc, Mountain View, CA, USA and MIRAS; Invatec S.r.l., Roncadelle, Italy).The tumours were considered as ablated completely if no viability was found on dual-phase dynamic contrast-enhanced CT at 1 month after RFA.

RESULTS

Complete ablation was obtained in 89.7% (88/98) of the high-risk located lesions, while 10 (10.3%) of the lesions were managed with repeated RFA because of tumour residue. The 1-, 2- and 3-year survival rates were 82.6, 67.3 and 54.1%, respectively. Minor complications occurred in eight of the 84 patients (9.5%), including small sub-capsular haematoma in four, small pleural effusion in three and partial liver infarction in one. Local tumour progression rate was 9.2% (9/98).

CONCLUSION

RFA is a safe and effective method of treatment of primary and metastatic liver tumours even located in challenging locations when performed by a well-trained and experienced interventional radiologist.

[Results of percutaneous radiofrequency ablation of hepatocellular carcinoma in patients with cirrhosis aged 75 years and over]

PURPOSE

The objective of this study was to assess the results and tolerance of radiofrequency ablation in patients with cirrhosis and hepatocellular carcinoma (HCC) older than 75 years.

PATIENTS AND METHODS

Over a period of 9 years from January 2001, 235 patients with cirrhosis and 3 or less HCC≤5 cm of diameter were treated by radiofrequency ablation. Among them, 52 patients older than 75 years were selected for this study.

RESULTS

The mean age was 79.4±3. 5 years. There were 36 males, cirrhosis was classified Child-Pugh class A (n=52) related to alcohol (n=13), HCV infection (n=33), or other causes (n=6). The mean tumour diameter was 32.5±10.6 mm, and 14 patients had a multifocal HCC. A complete ablation was obtained in 50/52 patients (96%). No severe complication occurred. The estimated overall survival rates were 62%, 52% and 36% at 3 years, 4 years and 5 years, respectively; it was similar to those observed in patients younger than 75 years.

CONCLUSION

In patients with cirrhosis older than 75 years, radiofrequency ablation of 3 or less HCC≤5cm is well tolerated and survivals rates are similar to those of younger patients.