Combined percutaneous radiofrequency ablation and ethanol injection versus hepatic resection for 2.1–5.0 cm solitary hepatocellular carcinoma: a retrospective comparative multicentre study

Comparison of laparoscopic hepatectomy and radiofrequency ablation for small hepatocellular carcinoma patients: a SEER population-based propensity score matching study

This study was designed to compare the efficacy of laparoscopic hepatectomy (LH) and radiofrequency ablation (RFA) in terms of their therapeutic effect on small hepatocellular carcinoma (SHCC). The SEER database was employed to integrate SHCC patients who had received treatment with either LH (n = 1132) or RFA (n = 797). The LH group (n = 623) and the RFA group (n = 623) were matched with 1:1 propensity score matching (PSM) in order to reduce the possibility of selection bias. The Kaplan-Meier method and Cox proportional hazards regression method were employed to ascertain the prognostic factors associated with overall survival (OS) and disease-specific survival (DSS). Both before and after PSM, the 1, 3 and 5-years OS and DSS were significantly higher in the LH groups compared to the RFA group. Besides, for SHCC with tumor size ≤ 2cm (n = 418), even P values not reaching statistical significance, the survival curves were compatible with a superiority of LH over RFA for OS and DSS in overall (P = 0.054 and P = 0.077), primary SHCC (P = 0.110 and P = 0.058) and recurrent SHCC (P = 0.068 and P = 1.000) cohorts. In contrast, for SHCC with tumor size between 2 and 3 cm (n = 828), LH group always had a better OS and DSS in the all cohorts (all P < 0.05). In addition, higher AFP level, poor differentiation grade, recurrent tumor and treatment type were independent prognostic factors for OS, while poor differentiation grade, larger tumor size and treatment type were the independent prognostic factors for DSS (all P < 0.05). LH was associated with better OS and DSS than RFA in SHCC patients. Even in tumor size ≤ 2 cm, LH still should be the first choice as its long-term survival benefits.

Ablative strategies for recurrent hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and is the fifth leading cause of cancer death worldwide and the third leading cause of all diseases worldwide. Liver transplantation, surgical resection and ablation are the three main curative treatments for HCC. Liver transplantation is the optimal treatment option for HCC, but its usage is limited by the shortage of liver sources. Surgical resection is considered the first choice for early-stage HCC, but it does not apply to patients with poor liver function. Therefore, more and more doctors choose ablation for HCC. However, intrahepatic recurrence occurs in up to 70% patients within 5 years after initial treatment. For patients with oligo recurrence after primary treatment, repeated resection and local ablation are both alternative. Only 20% patients with recurrent HCC (rHCC) indicate repeated surgical resection because of limitations in liver function, tumor location and intraperitoneal adhesions. Local ablation has become an option for the waiting period when liver transplantation is unavailable. For patients with intrahepatic recurrence after liver transplantation, local ablation can reduce the tumor burden and prepare them for liver transplantation. This review systematically describes the various ablation treatments for rHCC, including radiofrequency ablation, microwave ablation, laser ablation, high-intensity focused ultrasound ablation, cryablation, irreversible electroporation, percutaneous ethanol injection, and the combination of ablation and other treatment modalities.

The role of neoadjuvant conventional transarterial chemoembolization with radiofrequency ablation in the treatment of recurrent hepatocellular carcinoma after initial hepatectomy with microvascular invasion

OBJECTIVES

Recurrent hepatocellular carcinoma (HCC) patients with microvascular invasion (MVI)-positive primary tumor is at high risk of re-recurrence while treated with radiofrequency ablation (RFA). We aimed to investigate whether neoadjuvant conventional transarterial chemoembolization (cTACE) was effective in reducing re-recurrence after RFA for recurrent HCC patients with MVI-positive primary tumors.

METHODS

In this retrospective multicenter study, 468 patients with solitary small recurrent HCC (≤3.0cm) underwent RFA alone (n = 322) or with neoadjuvant cTACE (n = 146) between June 2007 and December 2017 were included. Overall survival (OS) and recurrence-free survival (RFS) were compared.

RESULTS

The 1-, 5-year OS rates were 74.8%, 42.5% for RFA with neoadjuvant cTACE group, and 53.5%, 28.7% for RFA group (P < 0.001). The corresponding RFS rates were 51.7%, 24.4% for RFA with neoadjuvant cTACE group, and 36.1%, 9.3% for RFA group (P < 0.001). In subgroup analyses, the OS and RFS for neoadjuvant cTACE group were longer than those for RFA group no matter tumor size > 2cm (HR = 0.52, 95% CI: 0.36-0.77; HR = 0.49, 95% CI: 0.36-0.67) or not (HR = 0.53, 95% CI: 0.32-0.88; HR = 0.65, 95% CI: 0.42-0.98), or the time interval of recurrence from initial treatment ≤ 1 year (HR = 0.53, 95% CI: 0.36-0.77; HR = 0.70, 95% CI: 0.52-0.94) or not (HR = 0.56, 95% CI: 0.34-0.95; HR = 0.39, 95% CI: 0.25-0.62). Multivariable analyses showed that RFA alone (HR = 1.329, P = 0.031; HR = 1.764, P = 0.004) and interval of recurrence from initial treatment > 1 year(HR = 0.642, P = 0.001; HR = 0.298, P = 0.037) were independent prognostic factors of OS and RFS.

CONCLUSIONS

Neoadjuvant cTACE could effectively reduce re-recurrence after RFA, and improve the long-term survivals for patients with solitary small recurrent HCC whose primary tumor was MVI-positive. Key pointsFor recurrent hepatocellular carcinoma (HCC) patients whose primary tumor was positive for microvascular invasion, neoadjuvant conventional transarterial chemoembolization (cTACE) with radiofrequency ablation (RFA) achieved better efficacy.Multivariable analyses showed that the interval of recurrence from initial treatment > 1 year and RFA alone were independent prognostic factors of overall survival and recurrence-free survival, respectively.

Suppression of Local Tumor Progression in Perivascular Hepatocellular Carcinoma by Combination Therapy with Radiofrequency Ablation and Percutaneous Ethanol Injection: A Propensity Score Matching Analysis

Background and Aims Radiofrequency ablation (RFA) has replaced percutaneous ethanol injection (PEI) as the treatment of choice for hepatocellular carcinoma (HCC); however, control of local tumor progression (LTP) remains a challenge in perivascular HCC. The aim of this study is to determine whether PEI added to RFA can reduce the LTP rate in perivascular HCC patients. Methods We retrospectively analyzed 167 patients, with 197 newly diagnosed HCC nodules with peritumoral vessels, who underwent either RFA plus PEI or RFA monotherapy as the first-line treatment between June 2001 and April 2015. Ethanol was injected inside the tumor close to the peritumoral vessels in the combination therapy group. Patients were matched 1:1 according to their propensity scores to reduce selection bias; cumulative LTP was then analyzed using log-rank tests and Cox proportional hazard regression analyses. Results The two matched groups comprised 62 tumors each. The overall median follow-up period was 34 months (range, 1-140 months). In the RFA plus PEI group, the cumulative LTP rates were 5.7%, 15.5%, and 20.4% at 1, 3, and 5 years, respectively; in the RFA monotherapy group, the rates were 13.2%, 32.0%, and 40.2%, respectively. The rates were significantly lower in the RFA plus PEI group (P = 0.032). Cox proportional hazard regression analysis showed that PEI combination treatment was significantly associated with a reduced risk of local HCC recurrence (hazard ratio, 0.44; 95% confidence interval, 0.19-0.93; P = 0.031). Discussion/Conclusion The risk of LTP after RFA for perivascular HCC can be significantly reduced by injecting ethanol close to the peritumoral vessels.

The safety and efficacy of percutaneous ethanol injection in the treatment of tumor thrombus in advanced hepatocellular carcinoma with portal vein tumor thrombus

OBJECTIVES

To compare the efficacy and safety of percutaneous ethanol injection (PEI) combined with transarterial chemoembolization (TACE + PEI) vs. TACE alone for the treatment of patients with advanced hepatocellular carcinoma (HCC) and portal vein tumor thrombus (PVTT).

METHODS

A total of 130 HCC patients with PVTT treated from May 2014 to August 2018 were retrospectively evaluated. Among them, 33 patients received TACE + PEI and 97 patients received TACE alone. PVTT was classified according to the Japanese Society of Hepatology; 97 patients had VP3 PVTT. Propensity score matching (PSM) was used to reduce selection bias.

RESULTS

Before PSM, the median overall survival (mOS) was 11 months (95% CI: 7.8-14.2) in the TACE + PEI group and 6 months (95% CI: 5.1-6.9) in the TACE group (p < 0.001), and the median progression-free survival (mPFS) was 5 months (95% CI: 3.7-6.3) in the TACE + PEI group and 2.5 months (95% CI: 2.1-2.9) in the TACE group (p < 0.001). Similar results were seen after PSM. Subgroup analysis showed that in patients with tumors > 5 cm in diameter and the VP3 subgroup, TACE + PEI brought a significant survival advantage over TACE alone before and after PSM. In the adverse event analysis, severe abdominal pain and bleeding after operation were seen in more patients in the TACE + PEI group than in the TACE group before PSM (P < 0.05).

CONCLUSIONS

For HCC patients with PVTT (especially those with tumor diameters > 5 cm and grade VP3), TACE combined with PEI for HCC patients with PVTT is safe and may provide better survival outcomes.

Combined ablation-chemotherapy versus chemotherapy alone for pancreatic cancer with liver metastasis: a propensity score matching study

Objectives: To retrospectively assess the efficacy of combined ablation-chemotherapy in comparison to that of chemotherapy alone in patients with liver metastasized pancreatic ductal adenocarcinoma (lmPDAC).Methods: In total 104 patients with hepatic oligo metastasized PDAC were identified; among them, 74 patients underwent combined thermal ablation-chemotherapy, and 30 patients underwent chemotherapy alone. Through propensity score matching, 1:1 matching of the combined ablation-chemotherapy group and chemotherapy group was achieved. The primary endpoint of this study was overall survival (OS). Clinical and tumor-related factors affecting OS were also analyzed through univariate and multivariate analyses using the Cox risk model.Results: For patients treated with combined ablation-chemotherapy, the median OS was 10.77 months, while it was 5.77 months for patients treated with chemotherapy alone (P = 0.011). The survival benefit for patients treated with combined ablation-chemotherapy was still preserved in the matched cohort, with a median OS of 8.17 months compared to 5.77 months in the chemotherapy group. Univariate and multivariate analyses in the matched population also showed treatment with combined ablation-chemotherapy was an independent prognostic factor (P < 0.05).Conclusions: For patients with liver metastases from pancreatic cancer, the combined use of thermal ablation and systemic chemotherapy offers a chance for a better survival outcome.

Thermal ablation of medium-sized hepatocellular carcinomas using intraoperative ultrasound fusion imaging: A propensity score-matched analysis

OBJECTIVE

To explore the value of ultrasound fusion imaging for the thermal ablation of medium-sized hepatocellular carcinomas (HCCs).

MATERIALS AND METHODS

From December 2010 to June 2018, patients with medium-sized (3.1-5.0cm) HCCs who underwent radiofrequency ablation (RFA) or microwave ablation (MWA) with the assistance of ultrasound fusion imaging were enrolled in this retrospective study. Technical efficacy, local tumor progression (LTP), intrahepatic distant recurrence (IDR), overall survival (OS), tumor-free survival (TFS) and major complications were evaluated during the follow-up period. The therapeutic outcomes were compared between the RFA/MWA combined with trans-arterial chemoembolization (TACE) group and the RFA/MWA alone group with propensity-score matching (PSM) analysis.

RESULTS

A total of 112 patients with 115 medium-sized HCCs were finally enrolled in this study. The median duration of follow-up was 33 months (range, 2-104 months). The technique efficacy was 100% (115/115). The 1-, 3-, 5-year OS rates and TFS rates were 95.5%, 76.7%, 71.5% and 74.1%, 48.7%, 41.8%, respectively. The corresponding LTP rates and IDR rates were 5.4%, 7.3%, 7.3% and 21.8%, 46.9%, 50.3%, respectively. The incidence of major complications was 5.4% (6/112). After PSM analysis (19 patients in each group), the therapeutic outcomes, including the OS, TFS, and LTP rates, were comparable in the two groups (P > 0.05).

CONCLUSIONS

With the assistance of ultrasound fusion imaging, thermal ablation of medium-sized HCC could achieve a satisfactory local control rate and long-term survival. The outcomes were comparable in the stratified analysis between the RFA/MWA alone group and the RFA/MWA+TACE group after PSM analysis.

Percutaneous ethanol injection enhanced the efficacy of radiofrequency ablation in the treatment of HCC: an insight into the mechanism of ethanol action

PURPOSE

To discuss the possible reasons why percutaneous intratumoral ethanol injection (PEI) combined with radiofrequency ablation (RFA) to treat hepatocellular carcinoma (HCC) reduced the recurrence and metastasis compared with RFA alone.

MATERIALS AND METHODS

Forty VX2 tumor-bearing rabbits were randomly divided into four groups (n = 10): the PEI, RFA, PEI-RFA, and control groups. Five rabbits from each group were sacrificed on the 3rd and 7th days after ablation. The number of metastatic tumors in the lung was counted. The ablation volume was measured, and residual tumor specimens were prepared for hematoxylin and eosin staining and caspase-3, Ki-67, and VEGF immunohistochemical staining.

RESULTS

The volume of ablation in the PEI-RFA group was significantly larger than that in the RFA and PEI groups (p < 0.05). However, no significant differences in the number of lung metastases after ablation were observed among the groups (p > 0.05). The number of microthrombi in the PEI-RFA group was greater than that in the control and RFA groups (p < 0.001 and p < 0.05). The Ki-67 labeling index (LI) and H-score of VEGF in the PEI-RFA group were lower than those in the RFA group, while the H-score of caspase-3 was higher than that in the RFA group on the 7th day after ablation (p < 0.05).

CONCLUSION

PEI occluded blood vessels by inducing microthrombi formation, and thereby reducing heat dissipation and increasing the effect of RFA. More importantly, in comparison with an incomplete RFA, PEI-RFA inhibited the increase in the Ki-67 and VEGF expression levels and the decrease in the caspase-3 expression level to happen at some extent and therefore improved the prognosis.

The Learning Curve for Thermal Ablation of Liver Cancers: 4,363-Session Experience for a Single Central in 18 Years

This study aimed to explore the special efforts required to achieve proficiency in performing thermal ablation of liver cancers, including tumors in difficult locations, and clarify the effects of handing-down teaching on the corresponding process. Major complications of patients receiving percutaneous thermal ablation of liver cancer were analyzed. Polynomial fitting was used to describe the connection between major complication rates and special experience. Learning curve of major complications was plotted both for the whole group and for each operator, respectively. Tumors in difficult locations were further studied. A total of 4,363 thermal ablation sessions were included in this study. 143 of 4,363 patients had major complications, corresponding to an incidence rate of 3.27%. 806 thermal ablation sessions were performed for tumors in difficult locations. The major complication rate of these sessions is 6.33%. According to the trend of the learning curve of the 4363 patients, the experience of the whole group can be classified into five stages, that is, the high-risk, relatively stable, unstable, proficient and stable periods. A learning curve for an individual operator can be classified into the high-risk, proficient and stable periods. The major complication rates for the chronologically first, second and third operator of the group are 3.23, 3.35, and 3.31%, respectively. The special experience needed to bypass the first stage corresponds to 410, 510, and 440 sessions, the second stage, 1850, 850, and 870 sessions, by the three operators, respectively. The major complication rates for the tumors in difficult locations for the first, second and third operator were 7.04, 5.53, and 5.98%, respectively. For the tumors in difficult locations, the special experience needed to bypass the first stage corresponds to 150, 130, and 140 sessions, the second stage, 290, 175, and 185 sessions, by the three operators, respectively. In conclusion, the learning process of an operator percutaneous thermal ablation for liver cancer can be classified into three stages. The major complication rate for tumors in difficult locations were higher than that for all tumors. Handing-down teaching can make an operator arrive at the third stage earlier but not the second stage.

Impact of focused ultrasound on the ethanol ablation of VX2 liver tumours in rabbits

OBJECTIVES

In this study, a treatment combining ethanol ablation (EA) and focused ultrasound (FUS) was performed to investigate its synergistic ablation effect on normal liver and VX2 liver tumours in rabbits.

METHODS

A total of 59 healthy New Zealand white rabbits were included. For normal liver ablation, 39 animals were treated with FUS alone (n = 12), EA alone (n = 12), EA+FUS combination treatment (n = 12), or the control treatment (n = 3). The other 20 rabbits with implanted VX2 liver tumours were treated with EA alone (n = 10) or EA+FUS (n = 10). For FUS, the liver was exposed to 1 MHz FUS with an intensity of 33.0 W/cm² (I_SPTA) for 20 s. The EA group received an injection of absolute ethanol in the liver or liver tumours. For EA+FUS combination therapy, FUS was focused at the EA injection site, and both methods were carried out at the same time.

RESULTS

In normal liver tissues, the ablated volume treated by FUS combined with EA (1.46 ± 0.30 cm³) was approximately 3 times larger than that of EA alone (0.51 ± 0.17 cm³); in VX2 liver tumours, the tumour necrosis rate of the combination therapy was 90.27%, which was much higher than that of EA treatment (63.55%).

CONCLUSION

The combination of EA and FUS could effectively increase the liver ablation volume and induce more complete tumour necrosis.

KEY POINTS

• This study demonstrated a novel method for enhancing ethanol ablation and elucidated its potential to enhance percutaneous ethanol ablation (PEA) in a simple non-invasive way. • Ethanol excited by focused ultrasound (FUS) exposure tended to accumulate at the injection site, which could prevent ethanol from being washed out by the bloodstream. • The combination of EA and FUS could effectively increase the liver ablation volume and induce more complete tumour necrosis.

[Locoregional and local ablative treatment options for liver tumors]

Interventional radiology offers a large variety of locoregional and local ablative treatment options for liver tumors. These can be applied as stand-alone minimally invasive procedures or in combination with other treatment options and with curative as well as palliative intent depending on the respective tumor stage. This review article presents the various locoregional and local ablative treatment techniques and describes the clinical value in the treatment of hepatocellular carcinoma and intrahepatic cholangiocarcinoma.

Safety and Efficacy of Radiofrequency Ablation for Solitary Hepatocellular Carcinoma (3-5 cm): a Propensity Score Matching Cohort Study

BACKGROUND

We aim to investigate the safety and efficacy of radiofrequency ablation in the treatment of solitary hepatocellular carcinoma (3-5 cm) in comparison with surgical resection.

METHODS

Included in this study were 388 patients with primary and solitary hepatocellular carcinoma, of whom 196 patients underwent surgical resection and the other 192 patients received radiofrequency ablation. Clinicopathological characteristics, prognosis, post-treatment complications, hospital stay, and financial expenditures between the two groups were compared retrospectively.

RESULTS

The result of propensity score matching and subgroup analysis showed that the 1-, 3-, and 5-year overall survival and disease-free survival were comparable in patients with tumors of 3-4 cm in diameter between surgical resection and radiofrequency ablation groups. However, when the tumor size exceeded 4 cm in diameter, surgical resection exhibited a superior long-term prognosis compared with radiofrequency ablation. Nevertheless, hepatectomy was associated with high occurrences of postoperative complications, long hospital stay, and high hospitalization cost as compared with radiofrequency ablation. Further analysis of the relationship between tumor size and pathological features of hepatocellular carcinoma showed that tumors larger than 4 cm were positively correlated with a high rate of microvascular invasion and satellite nodule formation.

CONCLUSION

For solitary hepatocellular carcinoma of 3-4 cm in diameter, radiofrequency ablation could achieve a comparable prognosis with a low incidence of post-treatment complications and low hospitalization costs, while surgical resection is recommended for solitary hepatocellular carcinoma tumors of 4-5 cm in diameter when long-term prognosis is considered.

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.

Radiofrequency-Sensitive Longitudinal Relaxation Tuning Strategy Enabling the Visualization of Radiofrequency Ablation Intensified by Magnetic Composite

As a minimally invasive heat source, radiofrequency (RF) ablation still encounters potential damages to the surrounding normal tissues because of heat diffusion, high power, and long time. With a comprehensive understanding of the current state of the art on RF ablation, a magnetic composite using porous hollow iron oxide nanoparticles (HIONs) as carriers to load dl-menthol (DLM) has been engineered. This composite involves two protocols for enhancing RF ablation, that is, HION-mediated magnetothermal conversion in RF field and RF solidoid vaporation (RSV)-augmented inertial cavitation, respectively. A combined effect based on two protocols is found to improve energy transformation, and further, along with hydrophobic DLM-impeded heat diffusion, improve the energy utilization efficiency and significantly facilitate ex vivo and in vivo RF ablation. More significantly, in vitro and in vivo RSV processes and RSV-augmented inertial cavitation for RF ablation can be monitored by T₁-weighted magnetic resonance imaging (MRI) via an RF-sensitive longitudinal relaxation tuning strategy because the RSV process can deplete DLM and make HION carriers permeable to water molecules, consequently improving the longitudinal relaxation rate of HIONs and enhancing T₁-weighted MRI. Therefore, this RF-sensitive magnetic composite holds a great potential in lowering the power and time of RF ablation and improving its therapeutic safety.