Survival analysis of high-intensity focused ultrasound ablation in patients with small hepatocellular carcinoma

Tissue Ablation: Applications and Perspectives

Tissue ablation techniques have emerged as a critical component of modern medical practice and biomedical research, offering versatile solutions for treating various diseases and disorders. Percutaneous ablation is minimally invasive and offers numerous advantages over traditional surgery, such as shorter recovery times, reduced hospital stays, and decreased healthcare costs. Intra-procedural imaging during ablation also allows precise visualization of the treated tissue while minimizing injury to the surrounding normal tissues, reducing the risk of complications. Here, the mechanisms of tissue ablation and innovative energy delivery systems are explored, highlighting recent advancements that have reshaped the landscape of clinical practice. Current clinical challenges related to tissue ablation are also discussed, underlining unmet clinical needs for more advanced material-based approaches to improve the delivery of energy and pharmacology-based therapeutics.

Ablative and non-surgical therapies for early and very early hepatocellular carcinoma: a systematic review and network meta-analysis

Background

A wide range of ablative and non-surgical therapies are available for treating small hepatocellular carcinoma in patients with very early or early-stage disease and preserved liver function.

Objective

To review and compare the effectiveness of all current ablative and non-surgical therapies for patients with small hepatocellular carcinoma (≤ 3 cm).

Design

Systematic review and network meta-analysis.

Data sources

Nine databases (March 2021), two trial registries (April 2021) and reference lists of relevant systematic reviews.

Review methods

Eligible studies were randomised controlled trials of ablative and non-surgical therapies, versus any comparator, for small hepatocellular carcinoma. Randomised controlled trials were quality assessed using the Cochrane Risk of Bias 2 tool and mapped. The comparative effectiveness of therapies was assessed using network meta-analysis. A threshold analysis was used to identify which comparisons were sensitive to potential changes in the evidence. Where comparisons based on randomised controlled trial evidence were not robust or no randomised controlled trials were identified, a targeted systematic review of non-randomised, prospective comparative studies provided additional data for repeat network meta-analysis and threshold analysis. The feasibility of undertaking economic modelling was explored. A workshop with patients and clinicians was held to discuss the findings and identify key priorities for future research.

Results

Thirty-seven randomised controlled trials (with over 3700 relevant patients) were included in the review. The majority were conducted in China or Japan and most had a high risk of bias or some risk of bias concerns. The results of the network meta-analysis were uncertain for most comparisons. There was evidence that percutaneous ethanol injection is inferior to radiofrequency ablation for overall survival (hazard ratio 1.45, 95% credible interval 1.16 to 1.82), progression-free survival (hazard ratio 1.36, 95% credible interval 1.11 to 1.67), overall recurrence (relative risk 1.19, 95% credible interval 1.02 to 1.39) and local recurrence (relative risk 1.80, 95% credible interval 1.19 to 2.71). Percutaneous acid injection was also inferior to radiofrequency ablation for progression-free survival (hazard ratio 1.63, 95% credible interval 1.05 to 2.51). Threshold analysis showed that further evidence could plausibly change the result for some comparisons. Fourteen eligible non-randomised studies were identified (n ≥ 2316); twelve had a high risk of bias so were not included in updated network meta-analyses. Additional non-randomised data, made available by a clinical advisor, were also included (n = 303). There remained a high level of uncertainty in treatment rankings after the network meta-analyses were updated. However, the updated analyses suggested that microwave ablation and resection are superior to percutaneous ethanol injection and percutaneous acid injection for some outcomes. Further research on stereotactic ablative radiotherapy was recommended at the workshop, although it is only appropriate for certain patient subgroups, limiting opportunities for adequately powered trials.

Limitations

Many studies were small and of poor quality. No comparative studies were found for some therapies.

Conclusions

The existing evidence base has limitations; the uptake of specific ablative therapies in the United Kingdom appears to be based more on technological advancements and ease of use than strong evidence of clinical effectiveness. However, there is evidence that percutaneous ethanol injection and percutaneous acid injection are inferior to radiofrequency ablation, microwave ablation and resection.

Study registration

PROSPERO CRD42020221357.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment (HTA) programme (NIHR award ref: NIHR131224) and is published in full in Health Technology Assessment; Vol. 27, No. 29. See the NIHR Funding and Awards website for further award information.

High-intensity focused ultrasound versus transarterial chemoembolization for hepatocellular carcinoma: a meta-analysis

PURPOSE

The application of high-intensity focused ultrasound (HIFU) in hepatocellular carcinoma (HCC) was promising. However, whether the effect of HIFU is comparable with that of transarterial chemoembolization (TACE) has not been determined.

MATERIALS AND METHODS

PubMed, Embase, Cochrane Library, Web of Science, WanFang Data, CqVip, CNKI, and CBM databases were searched for randomized controlled trials (RCTs), cohort studies, and case-control studies. The methodological quality of each study was evaluated. When there is no statistical heterogeneity, the fixed effect model would be used to merge data. Otherwise, the random effect model would be utilized. Sensitivity analyses were conducted by excluding one study each time. Subgroup analyses were conducted based on age, sex, tumor number, relative number of the patients with Child-Pugh C grade in each group, the percentage of patients with Child-Pugh C grade in the whole study, and tumor load. Publication bias was evaluated by Egger's test and Begg's test.

RESULTS

Six cohort studies including 188 patients from HIFU group and 224 patients from TACE group were obtained for further analysis. The meta-analysis suggested HIFU and TACE showed no differences in postoperative 1-year overall survival (OS) rate, tumor response (including complete response, partial response, stable disease, and progressive disease), and postoperative complications. Moreover, compared with TACE, HIFU showed higher postoperative 6-month and 2-year OS rates. Subgroup analyses, meta regression analysis and sensitivity analyses indicated the findings above were reliable. Additionally, no potential publication bias was detected.

CONCLUSION

For HCC, when compared with TACE, HIFU might show comparable safety but better effect. Considering the limitations of current studies, more well-designed studies are needed to validate our conclusion.

The Hong Kong consensus statements on unresectable hepatocellular carcinoma: narrative review and update for 2021

Background and Objective

Hong Kong, like many parts of Asia, faces a high burden of hepatocellular carcinoma (HCC) caused by high endemic rates of hepatitis B virus infection. Hong Kong clinicians have developed a high level of expertise in HCC treatment across surgical, transarterial, ablative, radiotherapeutic and systemic modalities. This publication summarizes the latest evidence-based recommendations on how these modalities should be used.

Methods

In two meetings held in 2020, a multidisciplinary panel of surgeons, oncologists and interventional radiologists performed a narrative review of evidence on the management of HCC, with an emphasis on treatment of HCC not amenable to surgical resection. Close attention was paid to new evidence published since the previous version of these statements in 2018.

Key Content and Findings

The expert panel has formulated 60 consensus statements to guide the staging and treatment of unresectable HCC. Since the previous version of these statements, considerable additions have been made to the recommendations on use of targeted therapies and immunotherapies because of the large volume of new evidence.

Conclusions

Our consensus statements offer guidance on how to select HCC patients for surgical or non-surgical treatment and for choosing among non-surgical modalities for patients who are not candidates for resection. In particular, there is a need for more evidence to aid physicians in the selection of second-line systemic therapies, as currently most data are limited to patients with disease progression on first-line sorafenib.

Contrast-Enhanced Ultrasound Tumor Therapy With Abdominal Imaging Transducer

A diagnostic ultrasound machine add-on module (AOM) was created to enable an off-the-shelf abdominal imaging transducer to perform contrast-enhanced therapeutic ultrasound. The AOM creates plane-wave ultrasound through an abdominal imaging transducer targeting intravascular microbubbles within tumors. This therapeutic antivascular ultrasound (AVUS) causes heating and cavitation effects that destroy tumor vasculature and starves it of nutrients. The AOM can switch between therapeutic and imaging modes for monitoring AVUS treatment. The therapeutic capability of the AOM was validated in murine hepatocellular carcinomas (HCC) grown in adult mice. Contrast-enhanced ultrasound imaging performed before and after the therapeutic treatment evaluated the AVUS response to the treatment. The peak enhancement (PE), perfusion index (PI), and area under the curve (AUC) were measured for the control and AOM treatment groups. The AOM group showed a substantial decrease in these parameters compared to the control group. The difference between the pre- and post-therapy was significant, (p < 0.001) for the AOM group and not significant (p > 0.5) for the control group. Tumor temperatures increased markedly for the AOM group with a thermal dose (CEM43) of 124.8 (±2.5). Histochemical analysis of the excised HCC samples revealed several hemorrhagic pools in tumors from the AOM group, absent in the tumors of the control group. These results demonstrate the theranostic potential of the AOM to induce and monitor vascular disruption within murine tumors.

Image-Guided Percutaneous Ablation for Primary and Metastatic Tumors

Image-guided percutaneous ablation methods have been further developed during the recent two decades and have transformed the minimally invasive and precision features of treatment options targeting primary and metastatic tumors. They work by percutaneously introducing applicators to precisely destroy a tumor and offer much lower risks than conventional methods. There are usually shorter recovery periods, less bleeding, and more preservation of organ parenchyma, expanding the treatment options of patients with cancer who may not be eligible for resection. Image-guided ablation techniques are currently utilized for the treatment of primary and metastatic tumors in various organs including the liver, pancreas, kidneys, thyroid and parathyroid, prostate, lung, bone, and soft tissue. This article provides a brief review of the various imaging modalities and available ablation techniques and discusses their applications and associated complications in various organs.

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.

Percutaneous Therapies for Hepatocellular Carcinoma: Evolution of Liver Directed Therapies

Percutaneous ablation is a mainstay of treatment for early stage, unresectable hepatocellular carcinoma (HCC). Recent advances in technology have created multiple ablative modalities for treatment of this common malignancy. The purpose of this review is to familiarize readers with the technical and clinical aspects of both existing and emerging percutaneous treatment options for HCC.

Emerging Therapeutic Strategies for Brain Tumors

Nearly thirty thousand incidences of primary and 300 thousand incidences of metastatic brain cancer are diagnosed in the USA each year. It has a high mortality rate and is often unresponsive to the standard of care, which includes surgical resection, radiation, and chemotherapy. These treatment strategies are also hindered by their invasiveness and toxic effects on healthy cells and tissues. Furthermore, the blood-brain/tumor barrier severely limits delivery of anti-cancer therapeutics administered intravenously to brain tumors, resulting in poor tumor response to the treatment. There is a critical need to develop new approaches to brain cancer therapy that can overcome these limitations. Focused ultrasound has emerged as a modality that addresses many of these limitations and has the potential to alter the treatment paradigm for brain cancer. Ultrasound transmitted through the skull can be focused on tumors and used for targeted ablation or opening the vascular barriers for drug delivery. This review provides insight on the current status of these unique ultrasound techniques, different strategies of using this technique for brain cancer, experience in preclinical models, and potential for clinical translation. We also debate the safety perspective of these techniques and discuss potential avenues for future work in noninvasive planning, monitoring, and evaluation of the ultrasonic neurointervention.

Effect of Overpressure on Acoustic Emissions and Treated Tissue Histology in ex Vivo Bulk Ultrasound Ablation

Bulk ultrasound ablation is a thermal therapy approach in which tissue is heated by unfocused or weakly focused sonication (average intensities on the order of 100 W/cm²) to achieve coagulative necrosis within a few minutes exposure time. Assessing the role of bubble activity, including acoustic cavitation and tissue vaporization, in bulk ultrasound ablation may help in making bulk ultrasound ablation safer and more effective for clinical applications. Here, two series of ex vivo ablation trials were conducted to investigate the role of bubble activity and tissue vaporization in bulk ultrasound ablation. Fresh bovine liver tissue was ablated with unfocused, continuous-wave ultrasound using ultrasound image-ablate arrays sonicating at 31 W/cm² (0.9 MPa amplitude) for either 20 min at a frequency of 3.1 MHz or 10 min at 4.8 MHz. Tissue specimens were maintained at a static overpressure of either 0.52 or 1.2 MPa to suppress bubble activity and tissue vaporization or at atmospheric pressure for control groups. A passive cavitation detector was used to record subharmonic (1.55 or 2.4 MHz), broadband (1.2-1.5 MHz) and low-frequency (5-20 kHz) acoustic emissions. Treated tissue was stained with 2% triphenyl tetrazolium chloride to evaluate thermal lesion dimensions. Subharmonic emissions were significantly reduced in overpressure groups compared with control groups. Correlations observed between acoustic emissions and lesion dimensions were significant and positive for the 3.1-MHz series, but significant and negative for the 4.8-MHz series. The results indicate that for bulk ultrasound ablation, where both acoustic cavitation and tissue vaporization are possible, bubble activity can enhance ablation in the absence of tissue vaporization, but can reduce thermal lesion dimensions in the presence of vaporization.

A review on radiofrequency, microwave and high-intensity focused ultrasound ablations for hepatocellular carcinoma with cirrhosis

Importance

Hepatocellular carcinoma (HCC) is usually accompanied by liver cirrhosis, which makes treatment of this disease challenging. Liver transplantation theoretically provides an ultimate solution to the disease, but the maximal surgical stress and the scarcity of liver graft make this treatment option impossible for some patients. In an ideal situation, a treatment that is safe and effective should provide a better outcome for patients with the dilemma.

Objective

This article aims to give a comprehensive review of various types of loco-ablative treatment for HCC.

Evidence Review

Loco-ablative treatment bridges the gap between surgical resection and transarterial chemotherapy. Various types of ablative therapy have their unique ability, and evidence-based outcome analysis is the most important key to assisting clinicians to choose the most suitable treatment modality for their patients.

Findings

Radiofrequency ablation (RFA) has a relatively longer history and more evidence to support its effectiveness. Microwave ablation (MWA) is gaining momentum because of its shorter ablation time and consistent ablation zone. High-intensity focused ultrasound (HIFU) ablation is a relatively new technology that provides non-invasive treatment for patients with HCC. It has been carried out at centers of excellence and it is a safe and effective treatment option for selected patients with HCC and liver cirrhosis.

Conclusion and Relevance

Selective use of different loco-ablative therapies will enhance clinicians' treatment options for treatment of HCC.

Systematic review of the role of high intensity focused ultrasound (HIFU) in treating malignant lesions of the hepatobiliary system

BACKGROUND

High Intensity Focused Ultrasound (HIFU) is an emerging non-invasive, targeted treatment of malignancy. The aim of this review was to assess the efficacy, safety and optimal technical parameters of HIFU to treat malignant lesions of the hepatobiliary system.

METHODS

A systematic search of the English literature was performed until March 2020, interrogating Pubmed, Embase and Cochrane Library databases. The following key-words were input in various combinations: 'HIFU', 'High intensity focussed ultrasound', 'Hepatobiliary', 'Liver', 'Cancer' and 'Carcinoma'. Extracted content included: Application type, Exposure parameters, Patient demographics, and Treatment outcomes.

RESULTS

Twenty-four articles reported on the clinical use of HIFU in 940 individuals to treat malignant liver lesions. Twenty-one studies detailed the use of HIFU to treat hepatocellular carcinoma only. Mean tumour size was 5.1 cm. Across all studies, HIFU resulted in complete tumour ablation in 55% of patients. Data on technical parameters and the procedural structure was very heterogeneous. Ten studies (n = 537 (57%) patients) described the use of HIFU alongside other modalities including TACE, RFA and PEI; 66% of which resulted in complete tumour ablation. Most common complications were skin burns (15%), local pain (5%) and fever (2%).

CONCLUSION

HIFU has demonstrated benefit as a treatment modality for malignant lesions of the hepatobiliary system. Combining HIFU with other ablative therapies, particularly TACE, increases the efficacy without increasing complications. Future human clinical studies are required to determine the optimal treatment parameters, better define outcomes and explore the risks and benefits of combination therapies.

Feasibility of High-Intensity Focused Ultrasound for Hepatocellular Carcinoma after Stereotactic Body Radiation Therapy: Initial Experience

The purpose of this initial clinical observation was to investigate the safety and effect of high-intensity focused ultrasound (HIFU) for patients with hepatocellular carcinoma (HCC) after stereotactic body radiation therapy (SBRT). Twenty patients who had been treated with SBRT, with 24 local residuals, received HIFU ablation. The changes of periphery blood cell count and serum biochemistry were observed before HIFU and 1 week after. Contrast-enhanced magnetic resonance imaging before HIFU and 2 weeks after was performed to assess the effect of HIFU. All patients received follow-up. The mean ± standard deviation follow-up time was 19.3 ± 18.0 mo. The median survival time and 1-y survival rate were 21 mo and 76.2%. Seventeen residual lesions (70.8%) received complete ablation and seven received partial ablation, with a mean ablation ratio of 75.8% ± 18.2%. No significant differences were found in periphery blood cell counts or serum biochemistry 1 week after HIFU compared with before HIFU. No severe adverse reactions related to HIFU were observed. Thus, we believe that HIFU can safely and effectively ablate residual HCC after SBRT, which may be a feasible option for patients with HCC who have local residuals after SBRT.

Recent progress in treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related death worldwide. In the past decade, there have been improvements in non-drug therapies and drug therapies for HCC treatment. Non-drug therapies include hepatic resection, liver transplantation, transarterial chemoembolization (TACE) and ablation. The former two surgical treatments are beneficial for patients with early and mid-stage HCC. As the first choice for non-surgical treatment, different TACE methods has been developed and widely used in combination therapy. Ablation has become an important alternative therapy for the treatment of small HCC or cases of unresectable surgery. Meanwhile, the drugs including small molecule targeted drugs like sorafenib and lenvatinib, monoclonal antibodies such as nivolumab are mainly used for the systematic treatment of advanced HCC. Besides strategies described above are recommended as first-line therapies due to their significant increase in mean overall survival, there are also potential drugs in clinical trials or under preclinical development. In addition, a number of potential preclinical surgical or adjuvant therapies are being studied, such as oncolytic virus, mesenchymal stem cells, biological clock, gut microbiome composition and peptide vaccine, all of which have shown different degrees of inhibition on HCC. With some potential anti-HCC drugs being reported, many promising therapeutic targets in related taxonomic signaling pathways including cell cycle, epigenetics, tyrosine kinase and so on that affect the progression of HCC have also been found. Together, the rational application of existing therapies and drugs as well as the new strategies will bring a bright future for the global cure of HCC in the coming decades.

Individualized Ablation of Hepatocellular Carcinoma: Tailored Approaches across the Phenotype Spectrum

Ablation is now recommended by international guidelines for the definitive treatment of hepatocellular carcinoma (HCC). Extensive clinical studies have demonstrated outcomes comparable to surgical resection with shorter hospital stays, decreased costs, and improved quality of life. Successful ablation requires complete treatment of both tumor and margin while preserving critical adjacent structures. HCC exhibits highly variable presentations in both anatomic involvement and biology which have significant implications on choice of ablative therapy. There are now abundant ablation modalities and adjunctive techniques which can be used to individualize ablation and maximize curative results. This article provides a patient-centered summary of approaches to HCC ablation in the context of patient performance, hepatic reserve, tumor phenotype and biology, intra- and extrahepatic anatomy, and ablation technology.

Preoperative MRI features and clinical laboratory indicators for predicting the early therapeutic response of hepatocellular carcinoma to transcatheter arterial chemoembolization combined with High-intensity focused ultrasound treatment

OBJECTIVES

To evaluate the value of preoperative MRI features and laboratory indicators in predicting the early response of hepatocellular carcinoma (HCC) to transcatheter arterial chemoembolization (TACE) combined with high-intensity focused ultrasound (HIFU) treatment and to establish a preoperative prediction model.

METHODS

A total of 188 patients with 223 tumors who underwent TACE/HIFU treatment from January 2011 to June 2017 were included. Tumors were divided into three groups (< 2 cm, 2 - 5 cm,> 5 cm) and classified as non-complete response (NCR) and complete response (CR) cohorts according to the Response Evaluation Criteria in Cancer of the Liver (RECICL) 2015 revised version. Univariate analysis and multivariate logistic regression analysis were used to determine independent predictors, and receiver operating characteristic (ROC) curve analysis was performed to assess the diagnostic power of each predictor. The prediction model was derived on the β coefficient of the multivariate regression analysis of the predictors.

RESULTS

Irregular margins in the 2 - 5 cm group were closely related to early NCR. Irregular margins, arterial peritumoral enhancement and abnormal alpha-fetoprotein (AFP) were independent predictors of early NCR in the > 5 cm group. The prediction model of this group suggests that irregular margins combined with arterial peritumoral enhancement and abnormal AFP combined with irregular margins and arterial peritumoral enhancement predict an increased risk of early NCR.

CONCLUSION

Irregular margins of 2 - 5 cm tumors and irregular margins, arterial peritumoral enhancement, and abnormal AFP of tumors > 5 cm can be applied to predict the early response of HCC to TACE/HIFU treatment.

ADVANCES IN KNOWLEDGE

TACE combined with HIFU treatment may be able to significantly improve survival in patients with advanced HCC. Conventional MRI features and laboratory indicators are readily available without complex post-processing. It is feasible to predict the response of HCC after TACE/HIFU treatment based on preoperative conventional MRI features and laboratory indicators, the combination of multiple features predicts high-risk of non-complete response.

Comparison of Combination Stereotactic Body Radiotherapy Plus High-Intensity Focused Ultrasound Ablation Versus Stereotactic Body Radiotherapy Alone for Massive Hepatocellular Carcinoma

Background

Thermal high-intensity focused ultrasound ablation is a non-invasive treatment of massive hepatocellular carcinomas. In stereotactic body radiotherapy, ablative radiotherapy is administered to tumors in targeted, limited doses to minimize damage to nearby tissues. We evaluated the outcomes and survival of patients receiving stereotactic body radiotherapy (singular therapy) versus those receiving combination thermal high-intensity focused ultrasound ablation plus stereotactic body radiotherapy (combination therapy).

Material/Methods

We compared data of 160 patients with massive hepatocellular carcinomas (12.5–18 cm) who were treated with combination therapy to those treated with singular therapy between January 2009 and February 2016.

Results

Eighty-four patients were treated with single therapy while 76 were treated with combination therapy. Comparison of short-term outcomes and long-term survival between the groups revealed no significant differences in adverse events. In the combination group, the proportions of patients with complete response, partial response, stable disease, and progressive disease were 52.6%, 21.1%, 21.1%, and 5.3%, respectively; in the single therapy group, the corresponding rates were 0%, 23.8%, 50%, and 26.2%, respectively (P<0.0001). The 1-year, 3-year, and 5-year survival rates in the combination group were 33%, 20%, and 13%, respectively, while those in the single therapy group were 21%, 14%, and 1%, respectively. These data indicated no differences in complications between the groups except for a significantly higher level of skin edema in the combination group (P=0.015).

Conclusions

Combination therapy is more effective than single therapy for the treatment of massive hepatocellular carcinomas, although rates of most complications appear to be similar.

Short-Term Observation of Ultrasonic Cyclocoagulation in Chinese Patients with End-Stage Refractory Glaucoma: A Retrospective Study

Purpose

To assess the efficacy and safety of HIFU-based ultrasonic cyclocoagulation in Chinese patients with end-stage refractory glaucoma.

Method

Patients were recruited consecutively from May 2016 to May 2017 in the Zhongshan Ophthalmic Center. Ultrasonic cyclocoagulation was performed on every patient, using the EyeOP1 ultrasound emitting device. Return visits were set at 1 day, 7 days, 1 month, and 3 months after the treatment. An intraocular pressure (IOP) reduction of ≥20% while IOP ≥ 5 mmHg was deemed as success. Mean IOP change was assessed. Efficacy of two modes (6 sectors and 8 sectors) was also compared. Complications were recorded for safety evaluation.

Results

61 eyes were treated in this study. The baseline IOP (mean ± SD) was 41.11 ± 10.65 mmHg. The percentage of IOP reduction after treatment was 29.2%, 43.2%, 34.8%, and 23.1% at 1 day, 7 days, 1 month, and 3 months, respectively. Overall success rate at 3 months was 50.0% (26/52). No significant difference was found between the 6 sectors group and the 8 sectors group in terms of the success rate (48.6% vs. 52.9%, p=0.768) as well as IOP reduction (p=0.417) at 3 months. Primary angle-closure glaucoma (PACG) had the highest success rate (80.0%, 12/15). Scleral thinning existed in 12 eyes, among which 2 developed hypotony (2 mmHg and 3 mmHg). Average pain score decreased massively compared with baseline data.

Conclusion

With high percentage of IOP reduction and a good safety profile observed in our study, HIFU-based ultrasonic cyclocoagulation might become a promising alternative to cyclodestructive methods. Long-term efficacy and safety need further assessment. The study was registered with Chinese Clinical Trial Registry (http://www.chictr.org.cn; Registration number: ChiCTR-OOC-17014028).

Value of texture analysis based on enhanced MRI for predicting an early therapeutic response to transcatheter arterial chemoembolisation combined with high-intensity focused ultrasound treatment in hepatocellular carcinoma

AIM

To evaluate the potential value of texture analysis (TA) based on contrast-enhanced magnetic resonance imaging (MRI) for predicting an early response of patients with hepatocellular carcinoma (HCC) who were treated with transcatheter arterial chemoembolisation (TACE) combined with high-intensity focused ultrasound (HIFU).

MATERIALS AND METHODS

Patients with HCC (n=89) who underwent contrast-enhanced MRI at 1.5 T 1 week before and 1 week, 1 month, and 3 months after TACE/HIFU were included in this retrospective study. Early responses were evaluated by two radiologists according to the Response Evaluation Criteria in Cancer of the Liver (RECICL). An independent Student's t-test and the Mann-Whitney U-test were used to compare the TA parameters between the complete response (CR) group and the non-complete response (NCR) group. Logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the predictive value of the NCR lesions.

RESULTS

Among the 89 patients, 58 showed CR and 31 showed NCR. Before TACE/HIFU, the CR group showed higher uniformity and energy but lower entropy than the NCR group (p<0.05). After TACE/HIFU, the CR group showed higher uniformity and energy but lower entropy and skewness than the NCR group (p<0.05). The logistic regression and ROC curve analyses showed that the entropy before TACE/HIFU and the skewness and entropy 1 week after TACE/HIFU were predictors of an early response.

CONCLUSION

TA parameters based on contrast-enhanced MRI images 1 week before and after TACE/HIFU may act as imaging biomarkers to predict an early response of patients with HCC.

Role of interventional radiology in managing pediatric liver tumors : Part 2: percutaneous interventions

Hepatoblastoma and hepatocellular carcinoma (HCC) are the most common pediatric liver malignancies, with hepatoblastoma occurring more commonly in younger children and HCC occurring more commonly in older children and adolescents. Although surgical resection (including transplant when necessary) and systemic chemotherapy have improved overall survival rate for hepatoblastoma to approximately 80% from 30%, a number of children with this tumor type are not eligible for operative treatment. In contradistinction, pediatric HCC continues to carry a dismal prognosis with an overall 5-year survival rate of 30%. The Paediatric Hepatic International Tumour Trial (PHITT) is an international trial aimed at evaluating both existing and emerging oncologic therapies for primary pediatric liver tumors. Interventional radiology offers a number of minimally invasive procedures that aid in diagnosis and therapy of pediatric liver tumors. For diagnosis, the PHITT biopsy guidelines emphasize and recommend percutaneous image-guided tumor biopsy. Additionally, both percutaneous and endovascular procedures provide therapeutic alternatives that have been, to this point, only minimally utilized in the pediatric population. Specifically, percutaneous ablation offers a number of cytotoxic technologies that can potentially eradicate disease or downstage children with unresectable disease. Percutaneous portal vein embolization is an additional minimally invasive procedure that might be useful to induce remnant liver hypertrophy prior to extended liver resection in the setting of a primary liver tumor. PHITT offers an opportunity to collect data from children treated with these emerging therapeutic options across the world. The purpose of this manuscript is to describe the potential role of minimally invasive percutaneous transhepatic procedures, as well as review the existing data largely stemming from the adult HCC experience.

Hong Kong Consensus Statements for the Management of Unresectable Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is highly prevalent in Hong Kong due to the high prevalence of chronic hepatitis B infection. Liver cancer is the fourth most common cancer and the third most common cause of cancer death. Due to the high case load, there is a high level of local expertise in treating HCC, and the full spectrum of treatment modalities is available. This document summarizes how these modalities should be used based on the latest evidence.

SUMMARY

In 2 meetings held in early 2017, a multidisciplinary group of Hong Kong clinicians, including liver surgeons, interventional radiologists, clinical oncologists, and medical oncologists, met to update local consensus statements for management of HCC. These statements are based on the latest evidence and give detailed guidance on how to deploy these modalities, in particular for cases of HCC which are not suited to surgical resection.

KEY MESSAGES

These statements give detailed information on how to decide if a patient is a candidate for resection, methods to improve candidacy for resection, and guidance for use of various nonsurgical interventions to manage patients ineligible for resection.

High intensity focused ultrasound (HIFU) applied to hepato-bilio-pancreatic and the digestive system-current state of the art and future perspectives

BACKGROUND

High intensity focused ultrasound (HIFU) is emerging as a valid minimally-invasive image-guided treatment of malignancies. We aimed to review to current state of the art of HIFU therapy applied to the digestive system and discuss some promising avenues of the technology.

METHODS

Pertinent studies were identified through PubMed and Embase search engines using the following keywords, combined in different ways: HIFU, esophagus, stomach, liver, pancreas, gallbladder, colon, rectum, and cancer. Experimental proof of the concept of endoluminal HIFU mucosa/submucosa ablation using a custom-made transducer has been obtained in vivo in the porcine model.

RESULTS

Forty-four studies reported on the clinical use of HIFU to treat liver lesions, while 19 series were found on HIFU treatment of pancreatic cancers and four studies included patients suffering from both liver and pancreatic cancers, reporting on a total of 1,682 and 823 cases for liver and pancreas, respectively. Only very limited comparative prospective studies have been reported.

CONCLUSIONS

Digestive system clinical applications of HIFU are limited to pancreatic and liver cancer. It is safe and well tolerated. The exact place in the hepatocellular carcinoma (HCC) management algorithm remains to be defined. HIFU seems to add clear survival advantages over trans arterial chemo embolization (TACE) alone and similar results when compared to radio frequency (RF). For pancreatic cancer, HIFU achieves consistent cancer-related pain relief. Further research is warranted to improve targeting accuracy and efficacy monitoring. Furthermore, additional work is required to transfer this technology on appealing treatments such as endoscopic HIFU-based therapies.

Early experience: high-intensity focused ultrasound treatment for intra-abdominal aggressive fibromatosis of failure in surgery

OBJECTIVE

The study was conducted to describe ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation in the treatment of intra-abdominal aggressive fibromatosis in seven patients who had failed surgery.

METHODS

We retrospectively investigated seven patients with pathologically proven intra-abdominal aggressive fibromatosis and surgical failure, who were treated with USgHIFU between June 2013 and February 2015. The main causes for surgical failure were a large tumour size or adjacent tissue invasion by the tumour. All of the patients were treated with palliative intent, to reduce symptoms of the diseases. The medical records were reviewed during the follow-up period, and the patients were asked to compare the symptoms of their disease as improved, unchanged or worsened, based on their levels before treatment. In addition, contrast-enhanced MRI was conducted to follow the size of the tumours before and after therapy.

RESULTS

The procedure was successfully accomplished in all of the patients without severe side effects. The median diameter of the tumours was 10.3 cm (range, 7.6-13.6 cm) and the mean ablation rate (the percentage rate of the non-perfused volume compared with the tumour volume on enhanced MRI after treatment) was 92.5 ± 3.7% (range, 86.5-96.8%). One patient underwent two treatments for a large tumour size, and other patients received single-visit therapy. All of the patient clinical symptoms remitted significantly after 6 months. The regression rates of the tumours were 34.8 ± 8.2% (range, 22.4-46.1%) and 58.2 ± 12.7% (range, 43.8-70.3%), respectively, at 6 and 12 months after treatment.

CONCLUSION

USgHIFU ablation could be an effective alternative minimally invasive therapy for the achievement of local control of intra-abdominal aggressive fibromatosis.

ADVANCES IN KNOWLEDGE

The conclusions indicate that USgHIFU ablation could be a promising alternative treatment for the achievement of local control of intra-abdominal aggressive fibromatosis.

Hong Kong consensus recommendations on the management of hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is particularly prevalent in Hong Kong because of the high prevalence of chronic hepatitis B (CHB) infection; HCC is the fourth commonest cancer in men and the seventh commonest in women, and it is the third leading cause of cancer death in Hong Kong. The full spectrum of treatment modalities for HCC is available locally; however, there is currently no local consensus document detailing how these modalities should be used.

SUMMARY

In a series of meetings held between May and October 2013, a multidisciplinary group of Hong Kong clinicians - liver surgeons, medical oncologists, clinical oncologists, hepatologists, and interventional radiologists - convened to formulate local recommendations on HCC management. These recommendations consolidate the most current evidence pertaining to HCC treatment modalities, together with the latest thinking of practicing clinicians engaged in HCC management, and give detailed guidance on how to deploy these modalities effectively for patients in various disease stages.

KEY MESSAGES

Distinct from other regional guidelines, these recommendations provide guidance on the use of antiviral therapy to reduce the incidence of HCC in CHB patients with cirrhosis and to reduce recurrence of CHB-related HCC.

Tumour eradication using synchronous thermal ablation and Hsp90 chemotherapy with protein engineered triblock biopolymer-geldanamycin conjugates

PURPOSE

Hepatocellular carcinoma (HCC) suffers high tumour recurrence rate after thermal ablation. Heat shock protein 90 (Hsp90) induced post-ablation is critical for tumour survival and progression. A combination therapy of thermal ablation and polymer conjugated Hsp90 chemotherapy was designed and evaluated for complete tumour eradication of HCC.

MATERIALS AND METHODS

A thermo-responsive, elastin-like polypeptide (ELP)-based tri-block biopolymer was developed and conjugated with a potent Hsp90 inhibitor, geldanamycin (GA). The anti-cancer efficacy of conjugates was evaluated in HCC cell cultures with and without hyperthermia (43 °C). The conjugates were also administered twice weekly in a murine HCC model as a single treatment or in combination with single electrocautery as the ablation method.

RESULTS

ELP-GA conjugates displayed enhanced cytotoxicity in vitro and effective heat shock inhibition under hyperthermia. The conjugates alone significantly slowed the tumour growth without systemic toxicity. Four doses of thermo-responsive ELP-GA conjugates with concomitant simple electrocautery accomplished significant Hsp90 inhibition and sustained tumour suppression.

CONCLUSION

Hsp90 inhibition plays a key role in preventing the recurrence of HCC, and the combination of ablation with targeted therapy holds great potential to improve prognosis and survival of HCC patients.

Survival analysis of high-intensity focused ultrasound therapy vs. transarterial chemoembolization for unresectable hepatocellular carcinomas

BACKGROUND & AIMS

High-intensity focused ultrasound (HIFU) ablation is a non-invasive treatment for unresectable hepatocellular carcinomas (HCCs), but long-term survival analysis is lacking. This study was to analyse its outcome compared to that of transarterial chemoembolization (TACE).

METHODS

From October 2003 to September 2010, 113 patients received HIFU ablation as a treatment of HCCs at our hospital. Twenty-six patients had HCCs sized 3-8 cm. Fifty-two patients with matched tumour characteristics having TACE as primary treatment were selected for comparison. Short-term outcome and long-term survival were analysed.

RESULTS

In the HIFU group (n = 26), 46 tumours were ablated. The median age of the patients was 69 (49-84) years. The median tumour size was 4.2 (3-8) cm. In the TACE group (n = 52), the median age of the patients was 67 (44-84) years. The median tumour size was 4.8 (3-8) cm. There was no hospital mortality in any of the groups. In the HIFU group, the rates of complete tumour response, partial tumour response, stable disease and progressive disease were 50%, 7.7%, 25.6% and 7.7% respectively, according to the modified Response Evaluation Criteria in Solid Tumours. The TACE group had the corresponding rates at 0%, 21.2%, 63.5% and 15.4% respectively (P < 0.0001). The 1-year, 3-year and 5-year survival rates were 84.6%, 49.2% and 32.3% respectively, in the HIFU group and 69.2%, 29.8% and 2.3% respectively, in the TACE group (P = 0.001).

CONCLUSION

HIFU ablation is a safe and effective method for unresectable HCCs. A survival benefit is observed over sole TACE.

Comparison of percutaneous ablation technologies in the treatment of malignant liver tumors

Tumor ablation is a minimally invasive technique used to deliver chemical, thermal, electrical, or ultrasonic damage to a specific focal tumor in an attempt to achieve substantial tumor destruction or complete eradication. As the technology continues to advance, several image-guided tumor ablations have emerged to effectively manage primary and secondary malignancies in the liver. Percutaneous chemical ablation is one of the oldest and most established techniques for treating small hepatocellular carcinomas. However, this technique has been largely replaced by newer modalities including radiofrequency ablation, microwave ablation, laser-induced interstitial thermotherapy, cryoablation, high-intensity-focused ultrasound ablation, and irreversible electroporation. Because there exist significant differences in underlying technological bases, understanding each mechanism of action is essential for achieving desirable outcomes. In this article, the authors review the current state of each ablation method including technological and clinical considerations.

Management of spontaneously ruptured hepatocellular carcinomas in the radiofrequency ablation era

BACKGROUND AND AIM

Spontaneous rupture of hepatocellular carcinoma (HCC) carries a high mortality. The use of radiofrequency ablation (RFA) in recent years has enriched the armamentarium for hemostasis of spontaneously ruptured HCCs but its results have not been documented. This study investigated the prognosis and outcome of spontaneous rupture of HCC as well as the results of using RFA for hemostasis.

PATIENTS AND METHOD

From January 1991 to December 2010, 5283 patients were diagnosed with HCC at our hospital, and 189 of them had spontaneous rupture of HCCs. They were grouped under two periods: period 1, 1991-2000, n = 70; period 2, 2001-2010, n = 119. RFA was available in period 2 only.

RESULTS

Hepatitis B virus infection was predominant in both periods. Surgical hemostasis was mainly achieved by hepatic artery ligation in period 1 and by RFA in period 2. The 30-day hospital mortality after surgical treatment was 55.6% (n = 18) in period 1 and 19.2% (n = 26) in period 2 (p = 0.012). Multivariate analysis identified 4 independent factors for better overall survival, namely, hemostasis by transarterial embolization [corrected] (hazard ratio 0.516, 95% confidence interval 0.354-0.751), hemostasis by RFA (hazard ratio 0.431, 95% confidence interval 0.236-0.790), having surgery as a subsequent treatment (hazard ratio 0.305, 95% confidence interval 0.186-0.498), and a serum total bilirubin level <19 umol/L (hazard ratio 1.596, 95% confidence interval 1.137-2.241).

CONCLUSION

The use of RFA for hemostasis during laparotomy greatly reduced the hospital mortality rate when compared with conventional hepatic artery ligation.