Hepatocellular carcinoma ≤ 4 cm treated with radiofrequency ablation with or without percutaneous ethanol injection

Image-guided locoregional non-intravascular interventional treatments for hepatocellular carcinoma: Current status

Hepatocellular carcinoma (HCC) is one of the most deadly and frequent cancers worldwide, although great advancement in the treatment of this malignancy have been made within the past few decades. It continues to be a major health issue due to an increasing incidence and a poor prognosis. The majority of patients have their HCC diagnosed at an intermediate or advanced stage in theUSA or China. Curative therapy such as surgical resection or liver transplantation is not considered anoption of treatment at these stages.

Transarterial chemoembolization (TACE), the most widely used locoregional therapeutic approach, used to be the mainstay of treatment for cases with unresectable cancer entities. However, for those patients with hypovascular tumors or impaired liver function reserve, TACE is a suboptimal treatment option. For example, embolization does not result in complete coverage of a hypovascular tumor, and may rather promotes postoperative tumor recurrence, or leave residual tumor, in these TACE-resistance patients. In addition, TACE carries a higher risk of hepatic decompensation in patients with poor liver function or reserve.

Non-vascular interventional locoregional therapies for HCC include radiofrequency ablation (RFA), microwave ablation (MWA), high-intensity focused ultrasound (HIFU), laser-induced thermotherapy (LITT), cryosurgical ablation (CSA), irreversible Electroporation (IRE), percutaneous ethanol injection (PEI), and brachytherapy. Recent advancements in these techniques have significantly improved the treatment efficacy of HCC and expanded the population of patients who qualify for treatment. This review embraces the current status of imaging-guided locoregional non-intravascular interventional treatments for HCCs, with a primary focus on the clinical evaluation and assessment of the efficacy of combined therapies using these interventional techniques.

The Islanding effect - a special method of percutaneous peritumor ethanol injection for hepatocellular carcinoma: 15-year follow-up outcome

Percutaneous ethanol injection is a well-known ablation therapy for hepatocellular carcinoma and is well-tolerated, inexpensive, and effective with few adverse events. In this study, another type of ethanol injection was introduced in the present study.Sixty two patients with hepatocellular carcinoma received 133 percutaneous peritumor ethanol injection treatments and the 15-year follow-up outcomes were analyzed through a collected database.The technical efficiency was 89.5% (119/133 treatments) after the first percutaneous peritumor ethanol injection procedure. However, after the second repeated percutaneous peritumor ethanol injection procedure, technical efficiency increased to 98.5% (131/133 treatments). The 1 year, 3 years, 5 years, 10 years, and 15 years rates of tumor recurrence were 12.9%, 50.0%, 59.7%, 74.2%, and 74.2%, respectively. Multivariate analysis demonstrated that diabetes, Child-Pugh class B, and tumor size greater than 2 cm were significantly related to tumor recurrence. The 1 year, 3 years, 5 years, 10 years, and 15 years rates of overall survival were 98.4%, 83.6%, 61.3%, 19.4%, and 0%, respectively. Multivariate analysis demonstrated that Child-Pugh class B, tumor size greater than 2 cm, and multiple tumors were significantly related to overall survival.Compared with other ablation methods (including peritumor ethanol injection), percutaneous peritumor ethanol injection can avoid tumor ruptures, reduce tumor proliferation and metastasis, and is suitable for the treatment of small tumors. In addition, when combined with other treatment methods, percutaneous peritumor ethanol injection can form a tumor metastatic isolation zone in advance and improve the comprehensive treatment effect.

Radiofrequency ablation with four electrodes as a building block for matrix radiofrequency ablation: Ex vivo liver experiments and finite element method modelling. Influence of electric and activation mode on coagulation size and geometry

PURPOSE

Radiofrequency ablation (RFA) is increasingly being used to treat unresectable liver tumors. Complete ablation of the tumor and a safety margin is necessary to prevent local recurrence. With current electrodes, size and shape of the ablation zone are highly variable leading to unsatisfactory local recurrence rates, especially for tumors >3 cm. In order to improve predictability, we recently developed a system with four simple electrodes with complete ablation in between the electrodes. This rather small but reliable ablation zone is considered as a building block for matrix radiofrequency ablation (MRFA). In the current study we explored the influence of the electric mode (monopolar or bipolar) and the activation mode (consecutive, simultaneous or switching) on the size and geometry of the ablation zone.

MATERIALS AND METHODS

The four electrode system was applied in ex vivo bovine liver. The electric and the activation mode were changed one by one, using constant power of 50 W in all experiments. Size and geometry of the ablation zone were measured. Finite element method (FEM) modelling of the experiment was performed.

RESULTS

In ex vivo liver, a complete and predictable coagulation zone of a 3 × 2 × 2 cm block was obtained most efficiently in the bipolar simultaneous mode due to the combination of the higher heating efficacy of the bipolar mode and the lower impedance by the simultaneous activation of four electrodes, as supported by the FEM simulation.

CONCLUSIONS

In ex vivo liver, the four electrode system used in a bipolar simultaneous mode offers the best perspectives as building block for MRFA. These results should be confirmed by in vivo experiments.

Appropriate treatment modality for solitary small hepatocellular carcinoma: Radiofrequency ablation vs. resection vs. transplantation?

There has been controversy regarding the first-line treatment modality for the patients who have small solitary hepatocellular carcinoma (HCC); radiofrequency ablation (RFA) or percutaneous ethanol injection (PEI), surgical hepatic resection (HR) and liver transplantation (LT). For selection of treatment modality of HCC, it should be considered of hepatic reservoir function as well as the tumor stage. If the liver function is good enough, HR may be the first choice regardless of the tumor size. However, recent studies comparing RFA with resection showed comparable outcome and similar survival rates. RFA, HR and LT provide good outcome for patients who have small HCCs. RFA would be desired in patients who have below 3.0 cm in size and low alpha-fetoprotein (<200 ng/mL). However, in small HCC with high tumor marker, HR should be considered. Better patient selection for the ‘resection first’ approach and early detection of recurrence can achieve better outcomes of the salvage LT strategy. Another benefit of resection first strategy is that it make possible to do enlist of LT for patients before recurrence at high risk of HCC recurrence after resection on the basis of pathologic aggressiveness, microvascular invasion and/or satellites nodule. They should be applied appropriately according to the tumor size, location, tumor markers and underlying liver parenchymal disease.

Comparison of radiofrequency ablation alone & in combination with percutaneous ethanol injection for management of hepatocellular carcinoma

Background & objective:

It has been shown that the combined use of alcohol before radiofrequency ablation (RFA) helps to augment the therapeutic advantage of RFA. The present study was conducted to compare the outcome of treatment with RFA alone and RFA with alcohol as ablative technique in patients with small hepatocellular carcinomas (HCCs), who were not candidates for surgery.

Methods:

Fifty patients with chronic liver disease and concurrent HCC were enrolled in this prospective study. The patients were treated with either RFA alone (n=25) or RFA combined with alcohol (n=25). Patient outcome was evaluated, and the tumour recurrence and survival of the patients were assessed in the two groups.

Results:

The survival rates at six months in patients who completed at least six months of follow up were 84 and 80 per cent in patients treated with RFA alone and combination therapy, respectively. During the follow up period, 11 and four patients treated with RFA alone showed local and distant intrahepatic tumour recurrence, respectively. All local recurrences were at one to 18 months of the follow up period. The distant recurrences occurred at 6-36 months of the follow up period. During the follow up period, eight and six patients treated with combination therapy showed local and distant intrahepatic tumour recurrence, respectively. All local recurrences were at 1.5-15 months during the follow up period. The distant intrahepatic recurrences occurred at 6-72 months during the follow up period.

Interpretation & conclusions:

No significant difference was seen between the survival time of the patients treated with RFA alone and RFA with alcohol as well as in the local recurrences and distant intrahepatic recurrences in RFA compared to RFA and alcohol group patients. Combined use of RFA and alcohol did not improve the local tumour control and survival in patients with HCC compared to RFA alone.

The local liver ablation with pulsed electric field stimulate systemic immune reaction against hepatocellular carcinoma (HCC) with time-dependent cytokine profile

AIM

How irreversible electroporation (IRE) affect immune status is still kept unknown. This preclinical study is to investigate its local and systemic immune reaction both on tumor-bearing and tumor free animals.

METHODS

Liver ablation was performed by a standard IRE instrument and proposal. Altogether 57 tumor bearing mice and 10 tumor-free porcine livers were ablated. The reaction of survival, radiology image, pathologically and immunologically were followed up. The detailed cytokines and chemokines responses were recorded dynamically post IRE ablation.

RESULTS

IRE ablation induced coagulation and necrosis in liver. It caused macrophages infiltration, in ablation zone. IRE ablation caused cellular inflammation. It, corrected the abnormal drifted Th2 in HCC back to Th1 status, promoting tumor eradication and host survival. The quantified cytokines and chemokines indicate IRE can stimulate both local immune reaction and systemic immune reaction.

CONCLUSION

Local IRE ablation changes the abnormal drifted Th2 in HCC back to Th1 status, facilitating tumor eradication and host survival.

Innovative Techniques for Image-Guided Ablation of Benign Thyroid Nodules: Combined Ethanol and Radiofrequency Ablation

In the treatment of benign thyroid nodules, ethanol ablation (EA), and radiofrequency ablation (RFA) have been suggested for cystic and solid thyroid nodules, respectively. Although combining these ablation techniques may be effective, no guidelines for or reviews of the combination have been published. Currently, there are three ways of combining EA and RFA: additional RFA is effective for treatment of incompletely resolved symptoms and solid residual portions of a thyroid nodule after EA. Additional EA can be performed for the residual unablated solid portion of a nodule after RFA if it is adjacent to critical structures (e.g., trachea, esophagus, and recurrent laryngeal nerve). In the concomitant procedure, ethanol is injected to control venous oozing after aspiration of cystic fluid prior to RFA of the remaining solid nodule.

Treatment of liver cancer of middle and advanced stages using ultrasound-guided percutaneous ethanol injection combined with radiofrequency ablation: A clinical analysis

Liver cancer is a malignancy of the digestive system and has a high morbidity and mortality rate. Local intervention has become a viable option in identifying liver treatment. The aim of the present study was to analyze the clinical effects of treating liver cancer in middle and advanced stages using ultrasound-guided percutaneous ethanol injection (PEI) in tumors combined with radiofrequency ablation (RFA). A total of 100 patients with stage III-IV liver cancers were selected to participate in the study. Patients were divided into groups. In group A, treatment was initiated with PEI and after 1-2 weeks RFA was applied while in group B treatment was initiated with RFA and after 1-2 weeks PEI was applied. Patients in group C received PEI and RFA simultaneously. The clinical effects in the 3 groups were compared after 6-month follow ups. The volume of tumor ablation necrosis in group A was significantly greater than that in the groups B and C, while the size was significantly smaller compared to groups B and C after ablation. For group A, the complete ablation rate was significantly higher than that in groups B and C, and the differences were statistically significant (P<0.05). Liver damage indices, including raising levels of glutamic-pyruvic transaminase and total bilirubin, were significantly decreased in group A (P<0.05). The survival rate in group A was also significantly higher than in groups B and C (P<0.05). In conclusion, for patients with liver cancer in middle and advanced stages, the treatment method using PEI followed by RFA was more beneficial in terms of improving the tumor ablation rate, alleviating liver damages and increasing survival rates.