Embolization of liver tumors: Past, present and future

Pathologic Complete Response After Gastric Artery Chemoembolization Combined With Tislelizumab for Neoadjuvant Therapy of Locally Advanced Gastric Cancer: A Case Report

Gastric cancer is the most common type of gastrointestinal cancer in China which about 80% of patients are locally advanced or advanced when diagnosed. Surgery along brings high recurrence rate for locally advanced gastric cancer (LAGC), and neoadjuvant therapies are needed. The use of programmed cell death-1 (PD-1)/programmed death-ligand 1 inhibitor nowadays improved the disease-free survival for LAGC, however, only <35% of patients achieved pathologic complete response (pCR) after neoadjuvant therapy nowadays. Therefore, new regimens are needed to be investigated. Gastric artery chemoembolization is applied to metastasis gastric cancer and researches showed interventional therapy can enhance the antitumor effect of PD-1 inhibitor. Here, for the first time, we combined gastric artery chemoembolization with tislelizumab (a PD-1 inhibitor) for neoadjuvant therapy of a patient with LAGC. The patient achieved pCR after a D2 resection and tumor regression grade score was 1. After surgery, the patient received tislelizumab 200 mg per 3 weeks, and showed no sign of recurrence after 6 months of follow-up. The study indicated the use of tislelizumab and gastric artery chemoembolization for neoadjuvant therapy may bring a better pCR rate and prognosis of LAGC.

Thrombin and Thrombin-Incorporated Biomaterials for Disease Treatments

Thrombin, a coagulation-inducing protease, has long been used in the hemostatic field. During the past decades, many other therapeutic uses of thrombin have been developed. For instance, burn treatment, pseudoaneurysm therapy, wound management, and tumor vascular infarction (or tumor vasculature blockade therapy) can all utilize the unique and powerful function of thrombin. Based on their therapeutic effects, many thrombin-associated products have been certificated by the Food and Drug Administration, including bovine thrombin, human thrombin, recombinant thrombin, fibrin glue, etc. Besides, several thrombin-based drugs are currently undergoing clinical trials. In this article, the therapeutic uses of thrombin (from the initial hemostasis to the latest cancer therapy), the commercially available drugs associated with thrombin, and the pros and cons of thrombin-based therapeutics (e.g., adverse immune responses related to bovine thrombin, thromboinflammation, and vasculogenic "rebounds") are summarized. Further, the current challenges and possible future research directions of thrombin-incorporated biomaterials and therapies are discussed. It is hoped that this review may provide a valuable reference for researchers in this field and help them to design safer and more effective thrombin-based drugs for fighting against various intractable diseases.

In vitro characteristics of Epirubicin-loaded thermosensitive liquid embolic agent

OBJECTIVE

To investigate the drug loading and release rate of epirubicin-loaded thermosensitive liquid embolic agents in vitro.

MATERIALS AND METHODS

The drug loading and stability of epirubicin-loaded thermosensitive liquid embolic agents with or without iopromide were determined by high-performance liquid chromatography, and the same method was used to determine the drug release rate of thermosensitive liquid embolic agents at different time points.

RESULTS

For epirubicin-loaded thermosensitive liquid embolic agents without iopromide, the average drug loading after filtration by membrane was (0.78 ± 0.02) mg and the drug loading rate was (16.1 ± 0.35)%, while the average drug loading without membrane was (0.73 ± 0.06) mg and the drug loading rate was (15.07 ± 1.17)%. After adding iopromide, the drug loading capacity was measured from 0 h-24 h solution and the drug loading was calculated indirectly and conclude that the drug loading capacity of thermosensitive liquid embolic agents decreased or disappeared. The sustained release rate of epirubicin from 0 to 48 hours was 42.65% in 48 hours.

CONCLUSION

Epirubicin can be successfully loaded into the thermosensitive liquid embolic agents with good stability and sustained release. After adding iopromide, the drug loading capacity of thermosensitive liquid embolic agents decreased or disappeared.

Association Between Preoperative Angioembolization and Bleeding Complications in Patients With Benign Liver Tumors: Analysis of a National Database

INTRODUCTION

The role of angioembolization (AE) in patients with benign liver diseases is an area of active research. This study aims to assess any difference in liver resection outcomes in patients with benign tumors dependent on utilization of preoperative AE.

METHODS

A retrospective cohort study of patients undergoing elective liver resections for benign liver tumors was performed using the National Surgical Quality Improvement Program database (2014-2019). Only tumors of 5 cm in size or more were included in the analysis. We categorized the patients based on preoperative AE (AE + versus AE -). The primary outcome measured included bleeding complications within 72 h. The secondary outcomes were to determine predictors of bleeding.

RESULTS

After propensity score matching, there were 103 patients in both groups. There was no difference in intraoperative or postoperative blood transfusions within 72 h of surgery (14.6% versus 12.6%; P = 0.68), reoperation (1.9% versus 1.9%; P = 1), or mortality (1.0% versus 0.0%; P = 1) between the two groups. Multivariate regression analysis revealed an open surgical approach (odds ratio [OR]: 4.59 confidence interval [CI]: 2.94-7.16), use of Pringle maneuver (OR: 1.7, CI: 1.26-2.310), preoperative anemia (OR: 2.79, CI: 2.05-3.80), and preoperative hypoalbuminemia (OR: 1.53 [1.14-2.05]) were associated with the need for intraoperative or postoperative blood transfusions within 72 h of surgery.

CONCLUSIONS

Preoperative AE was not associated with reducing intraoperative or postoperative bleeding complications or blood transfusions within 72 h after surgery.

Microfluidic Controllable Preparation of Iodine-131-Labeled Microspheres for Radioembolization Therapy of Liver Tumors

Transcatheter arterial radioembolization (TARE) is of great significance for the treatment of advanced hepatocellular carcinoma (HCC). However, the existing radioembolic microspheres still have problems such as non-degradability, non-uniform size, and inability to directly monitor in vivo, which hinders the development of TARE. In this paper, a novel radioembolic agent, 131 I-labeled methacrylated gelatin microspheres (131 I-GMs), is prepared for the treatment of HCC. Water-in-oil (W/O) emulsion templates are prepared by a simple one-step microfluidic method to obtain methacrylated gelatin microspheres (GMs) after UV irradiation. A series of GMs with uniform and controllable size is obtained by adjusting the flow rate of each fluid. Both air-dried and freeze-dried GMs can quickly restore their original shape and size, and still have good monodispersity, elasticity, and biocompatibility. The radiolabeling experiments show that 131 I can efficiently bind to GMs by chloramine-T method, and the obtained 131 I-GMs have good radioactive stability in vitro. The results of in vivo TARE treatment in rats show that 131 I-GMs can be well retained in the hepatic artery and have a good inhibitory effect on the progression of liver cancer, showing the potential for the treatment of HCC.

Intravoxel incoherent motion imaging used to assess tumor microvascular changes after transarterial chemoembolization in a rabbit VX2 liver tumor model

Purpose

To evaluate the correlation between microvascular density (MVD) and intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) parameters and the effect of glycolytic flux after transarterial chemoembolization (TACE) in a rabbit VX2 liver tumor.

Materials and methods

VX2 liver tumor allografts in 15 New Zealand white rabbits were treated with sterile saline (control group, n = 5) or lipiodol-doxorubicin emulsion (experimental group, n = 10). MRI was performed 2 weeks after the procedure to evaluate IVIM parameters, including apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (PF). All animal samples were taken of the tumor and surrounding liver. Immunostaining for CD31, CD34, CD105, and VEGF was used to evaluate MVD. The protein expression of Glut4, HK2, PKM2, LDHA, and MCT1 was determined using western blotting. Pearson correlation tests were used to analyze the relationship between MVD and IVIM parameters.

Results

D* value in the peritumoral region was negatively correlated with CD34 (r = -0.71, P = 0.01). PF value positively correlated with CD34 (r = 0.68, P = 0.015), CD105 (r = 0.76, P = 0.004) and VEGF (r = 0.72, P = 0.008) in the peritumoral region. Glut4, HK2, PKM2, and MCT1 in the peritumoral regions were higher in the experimental group than in the control group (all P < 0.05).

Conclusion

IVIM parameters were correlated with MVD in the intratumoral and peritumoral regions after TACE in a rabbit liver tumor model. The angiogenesis reflected by MVD may be related to changes of glycolytic flux.

Retrospective Comparative Study to Assess the Safety and Efficacy of Transradial Arterial Access for Hepatic Tumor Embolizations: A Single Operator Experience

Objectives To assess the efficacy and safety of transradial arterial access (TRA) for hepatic tumor embolizations and compare the outcomes between the TRA and transfemoral arterial access (TFA)

Materials and Methods A retrospective analysis of all consecutive hepatic tumor embolization procedures done through TFA or TRA by a single operator from November 2017 to April 2019 was performed. The procedural variables, including fluoroscopy time, radiation dose (reference air kerma [RAK]), conversion and complication rates, and patient preferences were recorded. The primary endpoint was technical success, which was defined as the successful completion of the embolization procedure. Procedural variables including radiation exposure and patient preferences, and complications were analyzed as secondary endpoints.

Results Out of 102 procedures in 90 patients, 44 were performed through TFA and the rest by TRA. A technical success rate of 98.2% and a crossover rate of 1.7% were recorded for TRA. There were no major vascular complications and similar rates of minor complications (8.6% for TRA, 2.3% for TFA; P = 0.055), without any clinical sequelae. After the initial learning curve, no significant differences for other procedural variables were noted between the two access sites. Faster ambulation were achieved following TRA (P < 0.055). All 12 patients who underwent repeat TACE after initial TRA chose this again over TFA.

Conclusions TRA is safe and effective for hepatic tumor embolization. Its safety and efficacy profile is comparable to that of TFA, with added improved patient comfort and faster ambulation.

Advances in Knowledge New catheter options and modifications of the existing techniques as explained in this article proved radial arterial access as a safe and effective alternative in hepatic arterial embolization.

The current status and future prospects for molecular imaging-guided precision surgery

Molecular imaging technologies are increasingly used to diagnose, monitor, and guide treatment of i.e., cancer. In this review, the current status and future prospects of the use of molecular imaging as an instrument to help realize precision surgery is addressed with focus on the main components that form the conceptual basis of intraoperative molecular imaging. Paramount for successful interventions is the relevance and accessibility of surgical targets. In addition, selection of the correct combination of imaging agents and modalities is critical to visualize both microscopic and bulk disease sites with high affinity and specificity. In this context developments within engineering/imaging physics continue to drive the growth of image-guided surgery. Particularly important herein is enhancement of sensitivity through improved contrast and spatial resolution, features that are critical if sites of cancer involvement are not to be overlooked during surgery. By facilitating the connection between surgical planning and surgical execution, digital surgery technologies such as computer-aided visualization nicely complement these technologies. The complexity of image guidance, combined with the plurality of technologies that are becoming available, also drives the need for evaluation mechanisms that can objectively score the impact that technologies exert on the performance of healthcare professionals and outcome improvement for patients.

Transarterial Chemoembolization and Unresectable Hepatocellular Carcinoma: A Narrative Review

Hepatocellular carcinoma (HCC) is an aggressive tumor, and even with the breakthrough in preventive strategies, and new diagnostic and treatment modalities, incidence and fatality rates continue to climb. Patients with HCC are most commonly diagnosed in the later stage, where the disease has already advanced, making it impossible to undertake potentially curative surgery. Transarterial chemoembolization (TACE) is a locoregional therapy regarded as a first-line treatment in patients with intermediate-stage HCC (Barcelona clinical liver cancer {BCLC}-B). TACE is a minimally invasive and non-surgical procedure that combines local chemotherapeutic drug administration with embolization to treat HCC. It helps limit tumor growth, preserve liver function, and increase overall and progression-free survival in patients with intermediate-stage HCC. This article has reviewed the efficacy, survival, limitations, and overall benefit of TACE in patients with unresectable HCC. This article has also discussed the effectiveness of TACE for neoadjuvant chemoembolization and the use of TACE with combination therapies.

Emerging Polymer Materials in Trackable Endovascular Embolization and Cell Delivery: From Hype to Hope

Minimally invasive endovascular embolization is a widely used clinical technique used for the occlusion of blood vessels to treat various diseases. Different occlusive agents ranging from gelatin foam to synthetic polymers such as poly(vinyl alcohol) (PVA) have been commercially used for embolization. However, these agents have some drawbacks, such as undesired toxicity and unintended and uncontrolled occlusion. To overcome these issues, several polymer-based embolic systems are under investigation including biocompatible and biodegradable microspheres, gelling liquid embolic with controlled occlusive features, and trackable microspheres with enhanced safety profiles. This review aims to summarize recent advances in current and emerging polymeric materials as embolization agents with varying material architectures. Furthermore, this review also explores the potential of combining injectable embolic agents and cell therapy to achieve more effective embolization with the promise of outstanding results in treating various devastating diseases. Finally, limitations and challenges in developing next-generation multifunctional embolic agents are discussed to promote advancement in this emerging field.

Safety of Image-Guided Treatment of the Liver with Ultrasound and Microbubbles in an in Vivo Porcine Model

Ultrasound and microbubbles are useful for both diagnostic imaging and targeted drug delivery, making them ideal conduits for theranostic interventions. Recent reports have indicated the preclinical success of microbubble cavitation for enhancement of chemotherapy in abdominal tumors; however, there have been limited studies and variable efficacy in clinical implementation of this technique. This is likely because in contrast to the high pressures and long cycle lengths seen in successful preclinical work, current clinical implementation of microbubble cavitation for drug delivery generally involves low acoustic pressures and short cycle lengths to fit within clinical guidelines. To translate the preclinical parameter space to clinical adoption, a relevant safety study in a healthy large animal is required. Therefore, the purpose of this work was to evaluate the safety of ultrasound cavitation treatment (USCTx) in a healthy porcine model using a modified Philips EPIQ with S5-1 as the focused source. We performed USCTx on eight healthy pigs and monitored health over the course of 1 wk. We then performed an acute study of USCTx to evaluate immediate tissue damage. Contrast-enhanced ultrasound exams were performed before and after each treatment to investigate perfusion changes within the treated areas, and blood and urine were evaluated for liver damage biomarkers. We illustrate, through quantitative analysis of contrast-enhanced ultrasound data, blood and urine analyses and histology, that this technique and the parameter space considered are safe within the time frame evaluated. With its safety confirmed using a clinical-grade ultrasound scanner and contrast agent, USCTx could be easily translated into clinical trials for improvement of chemotherapy delivery. This represents the first safety study assessing the bio-effects of microbubble cavitation from relevant ultrasound parameters in a large animal model.

Use of X-Ray Fluorescence Microscopy for Studies on Research Models of Hepatocellular Carcinoma

Introduction: TheraSphere^® microspheres containing yttrium ⁹⁰Y are among many radioembolization agents used clinically to reduce liver tumor burden, and their effects on cancer volume reduction are well-established. At the same time, concerns about off target tissue injury often limit their use. Deeper investigation into tissue distribution and long-term impact of these microspheres could inform us about additional ways to use them in practice.

Methods: Healthy rat liver and rabbit liver tumor samples from animals treated with TheraSpheres were sectioned and their elemental maps were generated by X-ray fluorescence microscopy (XFM) at the Advanced Photon Source (APS) synchrotron at Argonne National Laboratory (ANL).

Results: Elemental imaging allowed us to identify the presence and distribution of TheraSpheres in animal tissues without the need for additional sample manipulation or staining. Ionizing radiation produced by ⁹⁰Y radioactive contaminants present in these microspheres makes processing TheraSphere treated samples complex. Accumulation of microspheres in macrophages was observed.

Conclusions: This is the first study that used XFM to evaluate the location of microspheres and radionuclides in animal liver and tumor samples introduced through radioembolization. XFM has shown promise in expanding our understanding of radioembolization and could be used for investigation of human patient samples in the future.

Interplay of autophagy and cancer stem cells in hepatocellular carcinoma

Liver cancer is the sixth most common cancer and the fourth leading cause of cancer deaths in the world. The most common type of liver cancers is hepatocellular carcinoma (HCC). Autophagy is the cellular digestion of harmful components by sequestering the waste products into autophagosomes followed by lysosomal degradation for the maintenance of cellular homeostasis. The impairment of autophagy is highly associated with the development and progression of HCC although autophagy may be involved in tumour-suppressing cellular events. In regards to its protecting role, autophagy also shelters the cells from anoikis- a programmed cell death in anchorage-dependent cells detached from the surrounding extracellular matrix which facilitates metastasis in HCC. Liver cancer stem cells (LCSCs) have the ability for self-renewal and differentiation and are associated with the development and progression of HCC by regulating stemness, resistance and angiogenesis. Interestingly, autophagy is also known to regulate normal stem cells by promoting cellular survival and differentiation and maintaining cellular homeostasis. In this review, we discuss the basal autophagic mechanisms and double-faceted roles of autophagy as both tumour suppressor and tumour promoter in HCC, as well as its association with and contribution to self-renewal and differentiation of LCSCs.

Chinese expert consensus on technical recommendations for the standard operation of drug-eluting beads for transvascular embolization

Liver cancer is among the 10 most common tumors globally. In China, liver cancer ranks 4^th for prevalence and 3^rd for mortality among all malignant tumors. With respect to the treatment of primary liver cancer, there are a number of therapies currently available, including surgical resection, liver transplantation, ablation, transarterial chemoembolization (TACE), systemic chemotherapy, radiation therapy, targeted drug therapy and immunotherapy. Clinical practice and research have shown that, compared with conventional TACE (cTACE), drug-eluting bead TACE (DEB-TACE) can achieve a higher response rate and longer survival time in patients with primary liver cancer. Compared with that of cTACE, DEB-TACE has more favorable basic conditions for achieving uniformity, which could facilitate the standardization of operation techniques. China is the country with the highest incidence of primary liver cancer, accounting for more than 50% of the global patients, and its etiology and epidemiology in Chinese patients differ from those in Europeans and Americans. Therefore, experts in China have drafted these technical recommendations for the standard operation of drug-eluting beads for the treatment of liver cancer on the basis of accumulated abundant clinical experience and evidence-based medical data.

Ultrasound-visualized, site-specific vascular embolization using magnetic protein microcapsules

Imaging-guided vascular embolization is frequently performed on patients with advanced hepatocellular carcinoma (HCC) to alleviate symptoms and extend their survival time. Current operation procedures are not only painful for patients, but are also inaccurate in tumor targeting after the release of embolic agents from the catheter, leading to injury to healthy tissues simultaneously. In this study, we developed an ultrasound-visualized, site-specific vascular embolization strategy with magnetic protein microcapsules (MPMs). MPMs were fabricated using a rapid emulsification method, giving it a smooth surface and a core-shell structure. Their diameters could be controlled within 10 μm, allowing them to pass through capillaries. The core-shell structure and loading of magnetic Fe3O4 endowed MPMs with good contrast under ultrasound imaging and magnetically inducible targeting properties, as well as aggregation response even under flowing conditions. In vitro cytotoxicity and hemolysis evaluation demonstrated good biocompatibility of the MPMs. Furthermore, mock embolization showed that cell death could be induced by aggregation of the MPMs. Such a combination of real-time monitoring using ultrasound and control on targeted vascular embolization might be a breakthrough in the treatment of advanced HCC.

Employing hydrogels in tissue engineering approaches to boost conventional cancer-based research and therapies

Cancer is a complicated disease that involves the efforts of researchers to introduce and investigate novel successful treatments. Traditional cancer therapy approaches, especially chemotherapy, are prone to possible systemic side effects, such as the dysfunction of liver or kidney, neurological side effects and a decrease of bone marrow activity. Hydrogels, along with tissue engineering techniques, provide tremendous potential for scientists to overcome these issues through the release of drugs at the site of tumor. Hydrogels demonstrated competency as potent and stimulus-sensitive drug delivery systems for tumor removal, which is attributed to their unique features, including high water content, biocompatibility, and biodegradability. In addition, hydrogels have gained more attention as 3D models for easier and faster screening of cancer and tumors due to their potential in mimicking the extracellular matrix. Hydrogels as a reservoir can be loaded by an effective dosage of chemotherapeutic agents, and then deliver them to targets. In comparison to conventional procedures, hydrogels considerably decreased the total cost, duration of research, and treatment time. This study provides a general look into the potential role of hydrogels as a powerful tool to augment cancer studies for better analysis of cancerous cell functions, cell survival, angiogenesis, metastasis, and drug screening. Moreover, the upstanding application of drug delivery systems related to the hydrogel in order to sustain the release of desired drugs in the tumor cell-site were explored.

The Potential Gut Microbiota-Mediated Treatment Options for Liver Cancer

Primary liver cancer is one of the leading causes of cancer death worldwide. Surgical and non-surgical treatments are optional for liver cancer therapy based on the cancer stage. Accumulating studies show that the gut–liver axis influences the progression of liver diseases, including liver inflammation, fibrosis, cirrhosis, and cancer. However, the role of gut microbiota and their derived components and metabolites in liver cancer remains to be further clarified. In this review, we discuss the roles of gut microbiota and specific bacterial species in HCC and the strategies to modulate gut microbiota to improve antitumor therapy. Given the limitation of current treatments, gut microbiota-mediated therapy is a potential option for HCC treatment, including fiber diet and vegetable diet, antimicrobials, probiotics, and pharmaceutical inhibitors. Also, gut microbiota can be used as a marker for early diagnosis of HCC. HCC occurs dependent on various environmental and genetic factors, including diet and sex. Furthermore, gut microbiota impacts the immunotherapy of HCC treatment. Therefore, a better understanding of the role of the gut–liver axis in liver cancer is critically important to improve therapeutic efficacy.

Basics to advances in nanotherapy of colorectal cancer

Colorectal cancer (CRC) is the third most common cancer existing across the globe. It begins with the formation of polyps leading to the development of metastasis, especially in advanced stage patients, who necessitate intensive chemotherapy that usually results in a poor response and high morbidity owing to multidrug resistance and severe untoward effects to the non-cancerous cells. Advancements in the targeted drug delivery permit the targeting of tumor cells without affecting the non-tumor cells. Various nanocarriers such as liposomes, polymeric nanoparticles, carbon nanotubes, micelles, and nanogels, etc. are being developed and explored for effective delivery of cytotoxic drugs to the target site thereby enhancing the drug distribution and bioavailability, simultaneously subduing the side effects. Moreover, immunotherapy for CRC is being explored for last few decades. Few clinical trials have even potentially benefited patients suffering from CRC, still immunotherapy persists merely an experimental alternative. Assessment of the ongoing and completed trials is to be warranted for effective treatment of CRC. Scientists are paying efforts to develop novel carrier systems that may enhance the targeting potential of low therapeutic index chemo- and immune-therapeutics. Several preclinical studies have revealed the superior efficacy of nanotherapy in CRC as compared to conventional approaches. Clinical trials are being recruited to ascertain the safety and efficacy of CRC therapies. The present review discourses in a nutshell the molecular interventions including the genetics, signaling pathways involved in CRC, and advances in various strategies explored for the treatment of CRC with a special emphasis on nanocarriers based drug targeting.

DNA-nanorobot-guided thrombin-inducing tumor infarction: raising new potential clinical concerns

DNA-nanorobot-guided thrombin-inducing tumor infarction (DNA NanorobotTh-ITI) is emerging as a powerful therapeutic strategy for treatment of solid cancers. The technology represents a major advance in the application of DNA nanotechnology for anticancer therapy. More importantly, the technology is being translated from preclinical studies to the clinic owing to its promising anticancer effects with fewer toxicities demonstrated in preclinical settings. However, despite these beneficial effects of the technology, it is important to point out that some important potential clinical concerns remain to be addressed. Here, we raise these clinical concerns along with these beneficial effects of the technology. Hopefully, these newly raised potential clinical concerns could drive forward research in this field to expedite its clinical translation.

CalliSpheres Drug-Eluting Bead Transcatheter Arterial Chemoembolization Presents With Better Efficacy and Equal Safety Compared to Conventional TACE in Treating Patients With Hepatocellular Carcinoma

The aim of this study was to compare the treatment response, survival, liver function, and adverse event incidence of drug-eluting bead transcatheter arterial chemoembolization using CalliSpheres microspheres with conventional transcatheter arterial chemoembolization in patients with hepatocellular carcinoma. Seventy-three patients with hepatocellular carcinoma who received drug-eluting bead transcatheter arterial chemoembolization (using CalliSpheres microspheres) or conventional transcatheter arterial chemoembolization treatment were consecutively enrolled. Treatment response was assessed by modified Response Evaluation Criteria in Solid Tumors at month 1/month 3/month 6; posttreatment, liver function indexes, and adverse events were recorded. Progression-free survival and overall survival were also calculated. Objective response rate of patients at months 1, 3, and 6, disease control rate of patients and objective response rate of nodules at month 3 were increased in drug-eluting bead transcatheter arterial chemoembolization group compared with conventional transcatheter arterial chemoembolization group. In addition, drug-eluting bead transcatheter arterial chemoembolization using CalliSpheres microspheres was an independent factor for predicting better objective response rate at month 1. Patients in drug-eluting bead transcatheter arterial chemoembolization group achieved longer progression-free survival and similar overall survival compared to those in conventional transcatheter arterial chemoembolization group; Cox proportional hazards regression model analyses revealed that drug-eluting bead transcatheter arterial chemoembolization using CalliSpheres microspheres was associated with better progression-free survival while it did not affect overall survival. Meanwhile, most of the occurrences of abnormal liver function indexes were similar between 2 groups, whereas drug-eluting bead transcatheter arterial chemoembolization group had a higher percentage of patients with total bile acid ≥2 upper limit of normal compared to conventional transcatheter arterial chemoembolization group at month 1. Moreover, the adverse event incidences between 2 groups were similar. In conclusion, drug-eluting bead transcatheter arterial chemoembolization using CalliSpheres microspheres achieves better treatment response and progression-free survival while equal safety compared to conventional transcatheter arterial chemoembolization in patients with hepatocellular carcinoma.

Blocking transforming growth factor-beta reduces the migration and invasion of the residual tumour after TAE

This study aimed to investigate the treatment effects of combining TAE therapy with LY2109761, a transforming growth factor-beta (TGF-β) receptor I kinase inhibitor, on suppressing tumour growth and metastasis. We simulated the changing tumour microenvironment before and after TAE using both in vitro and in vivo models. In vitro, we evaluated the altered migration and invasion properties of HepG2 cells using migration and invasion assays. In addition, western blot analysis was used to investigate molecular mechanisms underlying the biological activities of LY2109761 in HepG2 cells. In vivo, we combined LY2109761 with TAE together in the VX2 rabbit model to evaluate the therapeutic effects of the combination. In vitro, the Smad pathway were substantially activated by hypoxia, and LY2109761 significantly inhibited the Smad pathway under both normoxic and hypoxic circumstances. Furthermore, LY2109761 inhibited cell proliferation, intravasation and metastasis by downregulating Smad-2 phosphorylation and up-regulating E-cadherin expression in both normoxic and hypoxic conditions. In addition, in animals, LY2109761 improved the therapeutic effect of TAE and inhibited intravasation and metastasis after TAE. Based on the observations herein, we concluded that using LY2109761 and TAE in combination for the treatment of VX2 rabbit liver cancer inhibits tumour growth and metastasis, suggesting that such a combination may provide new a target and strategy for interventional liver cancer therapy.

Exogenous sickle erythrocytes combined with vascular disruption trigger disseminated tumor vaso-occlusion and lung tumor regression

Hypoxic tumor niches are chief causes of treatment resistance and tumor recurrence. Sickle erythrocytes' (SSRBCs') intrinsic oxygen-sensing functionality empowers them to access such hypoxic niches wherein they form microaggregates that induce focal vessel closure. In search of measures to augment the scale of SSRBC-mediated tumor vaso-occlusion, we turned to the vascular disrupting agent, combretastatin A-4 (CA-4). CA-4 induces selective tumor endothelial injury, blood stasis, and hypoxia but fails to eliminate peripheral tumor foci. In this article, we show that introducing deoxygenated SSRBCs into tumor microvessels treated with CA-4 and sublethal radiation (SR) produces a massive surge of tumor vaso-occlusion and broadly propagated tumor infarctions that engulfs treatment-resistant hypoxic niches and eradicates established lung tumors. Tumor regression was histologically corroborated by significant treatment effect. Treated tumors displayed disseminated microvessels occluded by tightly packed SSRBCs along with widely distributed pimidazole-positive hypoxic tumor cells. Humanized HbS-knockin mice (SSKI) but not HbA-knockin mice (AAKI) showed a similar treatment response underscoring SSRBCs as the paramount tumoricidal effectors. Thus, CA-4-SR-remodeled tumor vessels license SSRBCs to produce an unprecedented surge of tumor vaso-occlusion and infarction that envelops treatment-resistant tumor niches resulting in complete tumor regression. Strategically deployed, these innovative tools constitute a major conceptual advance with compelling translational potential.

A Rare Case of a Ruptured Metastatic Hepatic Lesion from a Jejunal Gastrointestinal Stromal Tumor (GIST) Treated by Arterial Embolization

Patient: Male, 68

Final Diagnosis: Ruptured metastatic hepatic lesion from a jejunal GIST

Symptoms: Abdominal discomfort • hypotension

Medication: —

Clinical Procedure: —

Specialty: Gastroenterology and Hepatology

Transradial vs transfemoral access in patients with hepatic malignancy and undergoing hepatic interventions: A systematic review and meta-analysis

BACKGROUND

The aim of this study was to compare transradial access (TRA) approach with transfemoral access (TFA) approach in patients undergoing hepatic interventions.

METHODS

We conducted a comprehensive search of the PubMed, Embase, and the Cochrane Library database to identify relevant available articles. Patients' preference, success rate, intra- and postoperative outcomes were analyzed. The risk difference (RD), relative risk (RR), and weighted mean difference (WMD) values were reported with 95% confidence intervals (CIs). We used RevMan 5.3 to perform the pooled analyses.

RESULTS

Nine cohort studies were included. A total of 1096 procedures were performed in 877 patients. Of those, 545 procedures (49.7%) were performed by TRA, and 551 procedures (50.3%) were performed by TFA. Patients were significantly prefer the TRA (86.5%) to the TFA (13.5%) (RD = 0.88, P < .00001). The procedure time in TRA groups was longer (WMD = 3.36, 95% CI 1.24-5.47, P = .002). But there were no significant difference in terms of success rate, fluoroscopy time, radiation dosage, contrast volume, and postoperative vascular complications.

CONCLUSION

For patients suffer from primary or secondary hepatic malignancy and undergoing hepatic interventions, the present meta-analysis demonstrated that patients prefer the TRA approach to the TFA approach. But the procedure time is longer in TRA group.

Dynamic agent of an injectable and self-healing drug-loaded hydrogel for embolization therapy

Embolic agents are crucial for trans-catheter arterial embolization (TAE) in the treatment of various unresectable malignant tumors. Although solid particles, liquid oils, and some polymeric hydrogels have proved their capacities for embolic therapies, the low efficiency, time sensitivity, and cytotoxicity are still considered as challenges. In this study, we developed a three-component dynamic self-healing hydrogel to overcome these limitations. With the help of the Schiff-base bonding, both glycol-chitosan and carbazochrome, containing amine groups, react with dibenzaldehyde-terminated poly(ethylene-glycol) (DF-PEG), forming the dynamic self-healing hydrogels under a mild condition within 200 s. ¹H NMR and rheology test were used to characterize the Schiff-base formation and mechanical strength. Controlled-release of carbazochrome from different gelator concentrations of DF-PEG was also studied. Furthermore, in vivo evaluation of the embolization on rats showed the superior embolic effects of the injectable and self-healing hydrogel. Therefore, this new dynamic agent demonstrated the potential for application as a simple, inexpensive, and tunable embolic agent for cancer treatment and drug delivery system.

Embolization-induced Renal Tumor Shrinkage Followed by Definitive Cryoablation

Significant incidental findings reported on computed tomography (CT) scans are common. This article describes a 72-year-old man evaluated for possible bowel obstruction in whom was found a 3.1-cm x 2.6-cm centrally located enhancing mass in the left kidney highly suspicious for renal cell carcinoma. Due to substantial medical comorbidities, the patient was deemed a poor surgical candidate for either partial or complete nephrectomy. Interventional radiology was consulted for a minimally invasive ablation procedure. The large size and central location of the tumor involving the renal collecting system initially precluded definitive percutaneous cryoablation. Intra-arterial embolization was used as neoadjuvant therapy to decrease tumor burden. Fluoroscopy-guided bland embolization was performed targeting the arterial supply of the mass until stagnation of flow was achieved. A subsequent two-month post-embolization follow-up CT scan showed a 30% reduction in tumor size. Shrinkage of the mass from a central to a more peripheral location allowed for a cryoablation approach that would avoid damage to the vulnerable collecting system. Cryoablation was performed, and intraoperative CT demonstrated complete coverage of the tumor by the ice ball with no damage to the renal collecting system. A follow-up CT scan four years later showed no residual malignancy at the ablation site.

Complications of transarterial chemoembolization (TACE) in the treatment of liver tumors

INTRODUCTION

Transarterial chemoembolization (TACE) is considered a therapeutic option. It is mostly used in hepatocellular carcinoma or liver colorectal, neuroendocrine or melanoma metastases. Although it is considered a safe procedure, TACE presents complications, such as acute cholecystitis, which is the most common. Other procedure-related complications include pulmonary embolism, hepatic abscess, bile duct injury, gastric mucosa injury and, less frequently, acute pancreatitis. The aim of this study is to review the complications following TACE for liver tumors.

METHODS

We performed a retrospective study including all the TACE procedures performed in a single center during the period between January 2013 and December 2016.

RESULTS

Out of the 196 patients with liver tumors who had undergone 322 TACE, 258 (80%) were male and 64 (20%) were female. Mean patient age was 66.5years. Major complications after chemoembolization included: decompensation with edema/ascites (6patients), acute cholecystitis (4), acute pancreatitis (3), liver rupture (1), liver abscess (1) and renal failure (1). Postembolization syndrome appeared in 71 (20%) patients. On multivariate analysis, it was observed that concomitant cardiovascular disease (OR: 4.5; 95%CI: 1.2-17; P=.025) is a risk factor for the development of complications.

CONCLUSIONS

TACE is a safe and effective procedure for liver tumor treatment. The majority of the complications are rare and present a low incidence of mortality.

Computed tomography and histopathological findings after embolization with inherently radiopaque 40μm-microspheres, standard 40μm-microspheres and iodized oil in a porcine liver model

Purpose

The present study compared standard computed tomography (CT) and histopathological findings after endovascular embolization using a prototype of inherently radiopaque 40μm-microspheres with both standard 40μm-microspheres and iodized oil in a porcine liver model.

Materials and methods

Twelve pigs were divided into six study groups, of two pigs each. Four pigs were embolized with iodized oil alone and four with radiopaque microspheres; two animals in each group were sacrificed at 2 hours and two at 7 days. Two pigs were embolized with radiopaque microspheres and heparin and sacrificed at 7 days. Two pigs were embolized with standard microspheres and sacrificed at 2 hours. CT was performed before and after segmental embolization and before sacrifice at 7 days. The distribution of embolic agent, inflammatory response and tissue necrosis were assessed histopathologically.

Results

Radiopaque microspheres and iodized oil were visible on standard CT 2 hours and 7 days after embolization, showing qualitatively comparable arterial and parenchymal enhancement. Quantitatively, the enhancement was more intense for iodized oil. Standard microspheres, delivered without contrast, were not visible by imaging. Radiopaque and standard microspheres similarly occluded subsegmental and interlobular arteries and, to a lesser extent, sinusoids. Iodized oil resulted in the deepest penetration into sinusoids. Necrosis was always observed after embolization with microspheres, but never after embolization with iodized oil. The inflammatory response was mild to moderate for microspheres and moderate to severe for iodized oil.

Conclusion

Radiopaque 40μm-microspheres are visible on standard CT with qualitatively similar but quantitatively less intense enhancement compared to iodized oil, and with a tendency towards less of an inflammatory reaction than iodized oil. These microspheres also result in tissue necrosis, which was not observed after embolization with iodized oil. Both radiopaque and standard 40μm-microspheres are found within subsegmental and interlobar arteries, as well as in hepatic sinusoids.

Pharmacokinetics of continuous transarterial infusion of 5-fluorouracil in patients with advanced hepatocellular carcinoma

Numerous studies concerning hepatic arterial infusion chemotherapy (HAIC) have been conducted by adopting regimens containing 5-fluorouracil (FU), with a favourable efficacy compared with conventional transcatheter arterial chemoembolisation (TACE) treatment; however, the detailed mechanism of HAIC remains unclear. The present study aimed to evaluate peripheral concentration time curves of 5-FU administered through the hepatic artery, which may additionally explain the mechanism of action of HAIC. A total of 10 eligible patients underwent transcatheter arterial embolization and a 2-day HAIC treatment regimen using a folinic acid, fluorouracil and oxaliplatin regimen. Peripheral venous blood sampling was performed in each patient prior to infusion, and at 0, 0.5, 1, 1.5, 2, 5, 10, 15, 22 and 23 h following the start of infusion. The blood sample at 0 h was analysed for dihydropyrimidine dehydrogenase (DPD) levels by high performance liquid chromatography, and the rest of the samples were analysed for 5-FU by optimised liquid chromatography-mass spectrometry (LC-MS). The lower limit of quantification of optimised LC-MS for 5-FU was 5 ng/ml. The steady-state plasma concentration of 5-FU administered through the hepatic artery was achieved after 15 h. This concentration largely varied, ranging from 8.64-152.00 ng/ml. Optimised LC-MS may detect low concentrations of 5-FU. The steady-state concentration of 5-FU administered through the hepatic artery was achieved after 15 h. DPD levels were analysed through determining the ratio of plasma uracil (U) and dihydrouracil (UH2) by HPLC, and the results indicated a mild DPD deficiency in the patients with HCC. These results may provide a basis for the explanation of the clinical efficacy of HAIC, and to additionally optimise its efficacy.

Challenges in chemotherapy delivery: comparison of standard chemotherapy delivery to locoregional vascular mass fluid transfer

Standard intravenous chemotherapy delivery to neoplasms relies on simple diffusion gradients from the intravascular to the interstitial space. Systemic perfusion creates untoward effects on normal tissue limiting both concentration and exposure times. Regional intra-arterial therapy is limited by drug recirculation and vascular isolation repeatability and does not address the interstitial microenvironment. Barriers to delivery relate to chaotic vascular architecture, heterogeneous fluid flux, increased interstitial and variable solid tumor pressure and ischemia. To address these difficulties, a delivery system was developed allowing mass fluid transfer of chemotherapeutic agents into the interstitium. This implantable, reusable system is comprised of multiple independently steerable balloons and catheters capable of controlling the locoregional hydraulic and oncotic forces across the vascular endothelium.

High-Performance Poly(lactic-co-glycolic acid)-Magnetic Microspheres Prepared by Rotating Membrane Emulsification for Transcatheter Arterial Embolization and Magnetic Ablation in VX2 Liver Tumors

Interventional embolization is a popular minimally invasive vascular therapeutic technique and has been widely applied for hepatocellular carcinoma (HCC) therapy. However, harmful effects caused by transcatheter arterial chemoembolization (TACE) and radioembolization, such as the toxicity of chemotherapy or excessive radiation damage, are serious disadvantages and significantly reduce the therapeutic efficacy. Here, a synergistic therapeutic strategy combined transcatheter arterial embolization and magnetic ablation (TAEMA) by using poly(lactic-co-glycolic acid) (PLGA)-magnetic microspheres (MMs) has been successfully applied to orthotopic VX₂ liver tumors of rabbits. These MMs fabricated by novel rotating membrane emulsification system with well-controlled sizes (100-1000 μm) exhibited extremely low hemolysis ratio and excellent biocompatibility with HepG2 cells and L02 cells. Moreover, experimental results demonstrated that, while exposed to alternating magnetic field (AMF) after TAE, the tumor edge could be heated up by more than 15 °C both in vivo and in vitro, whereas only a negligible increase of temperature was observed in the normal hepatic parenchyma (NHP) nearby. Sufficient temperature increase induces apoptosis of tumor cells. This can further inhibit the tumor angiogenesis and results in necrosis compared to the rabbits only treated with TAE. In stark contrast, tumors rapidly grow and subtotal metastasis occurs in the lungs or kidneys, causing severe complications for rabbits only irradiated under AMF. Importantly, the results from the biochemical examination and the gene expression of relative HCC markers further confirmed that the treatment protocol using PLGA-MMs could achieve good biosafety and excellent therapeutic efficacy, which are promising for liver cancer therapy.

Mechanism of action and efficacy of LY2109761, a TGF-β receptor inhibitor, targeting tumor microenvironment in liver cancer after TACE

TACE (transcatheter arterial chemoembolization) has been recognized as an effective palliative treatment option for patients with HCC, however, the medium-long term efficacy of it remains modest. LY2109761, a TGF-β receptor inhibitor, was confirmed to reduce tumor cell growth, intravasation, and metastatic dissemination of HCC cells through different molecular mechanisms. This study aims to investigate the treatment effect of combining TACE therapy with LY2109761- a TGF-β receptor I kinase inhibitor on suppressing tumor growth and metastasis in a rabbit VX2 tumor model. The molecular mechanisms underlying the biological activities of LY2109761 was also evaluated through an in vitro model. And we found that LY2109761 could inhibit cell proliferation by down-regulating the phosphorylation of Smad-2 as well as improved the therapeutic effect of TACE in a VX2 hepatocellular carcinoma model. And we further found that LY2109761 may play a modulating role in the process of T cell transformation. Hence, based on those obsevations in our research, we concluded that combing LY2109761 with TACE for the treatment of VX2 rabbit liver cancer can help inhibit tumor growth as well as increase the tumor cell necrosis after TACE.

Clustering of Cyclodextrin-Functionalized Microbeads by an Amphiphilic Biopolymer: Real-Time Observation of Structures Resembling Blood Clots

Colloidal particles can be induced to cluster by adding polymers in a process called bridging flocculation. For bridging to occur, the polymer must bind strongly to the surfaces of adjacent particles, such as via electrostatic interactions. Here, we introduce a new system where bridging occurs due to specific interactions between the side chains of an amphiphilic polymer and supramolecules on the particle surface. The polymer is a hydrophobically modified chitosan (hmC) while the particles are uniform polymeric microbeads (∼160 μm in diameter) made by a microfluidic technique and functionalized on their surface by α-cyclodextrins (CDs). The CDs have hydrophobic binding pockets that can capture the n-alkyl hydrophobes present along the hmC chains. Clustering of CD-coated microbeads in water by hmC is visualized in real time using optical microscopy. Interestingly, the clustering follows two distinct stages: first, the microbeads are bridged into clusters by hmC chains, which occurs by the interaction of individual chains with the CDs on adjacent particles. Thereafter, additional hmC from the solution adsorbs onto the surfaces of the microbeads and an hmC "mesh" grows around the clusters. This growing nanostructured mesh can trap surrounding microsized objects and sequester them within the overall cluster. Such clustering is reminiscent of blood clotting where blood platelets initially cluster at a wound site, whereupon they induce growth of a protein (fibrin) mesh around the clusters, which entraps other passive cells. Clustering does not occur with the native chitosan (lacking hydrophobes) or with the bare particles (lacking CDs); these results confirm that the clustering is indeed due to hydrophobic interactions between the hmC and the CDs. Microbead clustering via amphiphilic biopolymers could be applicable in embolization, which is a surgical technique used to block blood flow to a particular area of the body, or in agglutination assays.

Selective internal radiation therapy using yttrium-90 resin microspheres in patients with unresectable hepatocellular carcinoma: a retrospective study

BACKGROUND

Selective internal radiation therapy (SIRT) with yttrium-90 resin (Y-90 resin) microspheres has been used as a locoregional therapy for patients with unresectable hepatocellular carcinoma (HCC). We examined patient and disease characteristics that might affect survival after Y-90 resin, as well as treatment tolerability.

METHODS

Data from patients with unresectable HCC treated with Y-90 resin at a single institution were reviewed retrospectively. Survival was assessed with Kaplan-Meier curves and log-rank tests. Response was evaluated with the response evaluation criteria in solid tumors (RECIST) criteria. Adverse events (AEs) were noted, and laboratory values were graded with CTCAE v3.0.

RESULTS

Data from 111 patients were analyzed. AEs occurred in 23 patients at 1 week after treatment and in 46 at 3 months. At 6 months, 13 patients had a complete response and 13 had a partial response. Factors associated with longer overall survival (OS) included early-stage disease [27.8 months for patients with Barcelona-Clinic Liver Cancer (BCLC) A vs. 9.2 months for BCLC C]; treatment with other locoregional therapies (69.0 vs. 11.4 months); and lack of bilobar disease (23.5 vs. 9.4 months), portal vein thrombosis (16.2 vs. 8.6 months), ascites (16.6 vs. 10.3 months), and treatment with sorafenib (17.2 vs. 10.3 months). In six patients, Y-90 resin was used as a bridge to liver transplantation, which greatly improved survival (69.0 vs. 12.1 months).

CONCLUSIONS

Several characteristics may prove useful for selecting patients likely to respond well to Y-90 resin. These results should be confirmed in prospective studies.

The role of hepatic trans-arterial chemoembolization in metastatic medullary thyroid carcinoma: a specialist center experience and review of the literature

BACKGROUND

Liver metastases are relatively common in patients with metastatic medullary thyroid carcinoma (MTC), carrying a negative impact on disease prognosis. The options for selective therapy of liver metastases in MTC patients are limited to catheter-guided procedures such as trans-arterial chemoembolization (TACE). Data regarding the effectiveness and safety of this procedure in MTC are limited.

AIM

To explore the clinical outcome, survival and safety profile of TACE for liver metastases in a group of MTC patients.

METHODS

Retrospective case series of patients treated at a single tertiary University Medical Center from 2005 to 2015.

RESULTS

Seven consecutive patients (mean age 64.5 ± 10.9 years, 5 females) with histologically confirmed MTC with liver metastases were included. Metastatic involvement of the liver was less than 50% of the liver volume in all patients. The median size of the largest liver lesion was 40 ± 6.9 mm. The patients underwent in total 20 sessions of TACE. Clinical improvement as well as tumor response (PR) were observed in all patients. The median time to tumor progression was 38 months (range 8-126). Three patients were still alive at the end of the follow-up period (a median overall survival rate of 57 ± 44 months).

CONCLUSION

TACE in MTC patients with hepatic metastases is usually well tolerated and induces both clinical improvement and tumor response for prolonged periods of time in the majority of patients. This therapeutic option should always be considered, irrespective of the presence of extrahepatic metastasis.

Liver Injury and Tumor-Inhibiting Effect of Sequential Transcatheter Arterial Chemoembolization and Portal Venous Embolization on Rabbit VX2 Liver Carcinoma

BACKGROUND The concepts of sequential transcatheter arterial chemoembolization (TACE) and portal venous embolization (PVE) were proposed to prevent the detrimental tumor growth-inducing effect of PVE and to facilitate growth of further future liver remnant (FLR). This study aimed to investigate the effect of sequential TACE and PVE on liver damage and the therapeutic effect in a rabbit VX2 liver tumor model. MATERIAL AND METHODS Rabbits bearing VX2 liver tumors were randomly divided into TACE+PVE, TACE, PVE, and Sham groups. Plasma levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (TBIL), and alkaline phosphatase (ALP) at 6 h, 24 h, 3 days, and 7 days were measured by ELISA assay. Tumor diameter on day 7 was measured and the tumor sections with cleaved caspase-3 was stained and observed. RESULTS Plasma ALT, AST, and ALP levels were significantly increased at the first hours after the interventions. The TACE group had higher increases than the TACE+PVE and PVE alone groups. ALT, AST, and ALP levels decreased on day 7 and presented a trend to return to the baseline level. The TACE+PVE group showed stronger tumor-inhibiting effect than the TACE and PVE alone groups and also induced the highest level of tumor cell apoptosis. CONCLUSIONS The liver damage caused by TACE+PVE is mild and recoverable. TACE+PVE showed stronger tumor-inhibiting effect than in the TACE and PVE group and also induced the highest level of tumor cell apoptosis.

Evaluation of efficacy of transcatheter arterial chemoembolization for hepatocellular carcinoma using magnetic resonance diffusion-weighted imaging

Although the efficacy of transcatheter arterial chemoembolization (TACE) has been recommended as first-line therapy for nonsurgical patients with hepatocellular carcinoma (HCC), it is difficult to accurately predict the efficacy of TACE. Therefore, this study evaluated the efficacy of TACE for HCC using magnetic resonance (MR) diffusion-weighted imaging (DWI). A total of 84 HCC patients who received initial TACE were selected and assigned to the stable group (n=39) and the progressive group (n=45). Before TACE treatment, a contrast-enhanced MR scan and DWI (b=300, 600, and 800 s/mm²) were performed on all patients. The modified response evaluation criteria in solid tumors were used for evaluation of tumor response. Receiver operating characteristic curve was employed to predict the value of apparent diffusion coefficient (ADC) for TACE efficacy. The ADC values of HCC patients in the progressive group were higher than those in the stable group at different b-values (b=300, 600, and 800 s/mm²) before TACE treatment. The area under the curve of ADC values with b-values of 300, 600, and 800 s/mm² were 0.693, 0.724, and 0.746; the threshold values were 1.94×10^-3 mm²/s, 1.28×10^-3 mm²/s, and 1.20×10^-3 mm²/s; the sensitivity values were 55.6%, 77.8%, and 73.3%; and the specificity values were 82.1%, 61.5%, and 71.8%, respectively. Our findings indicate that the ADC values of MR-DWI may accurately predict the efficacy of TACE in the treatment of HCC patients.

Comparative effectiveness of different transarterial embolization therapies alone or in combination with local ablative or adjuvant systemic treatments for unresectable hepatocellular carcinoma: A network meta-analysis of randomized controlled trials

BACKGROUND

The optimal transcatheter embolization strategy for patients with unresectable hepatocellular carcinoma (HCC) remains elusive. We conducted a systematic review and network meta-analysis (NMA) of different embolization options for unresectable HCC.

METHODS

Medical databases were searched for randomized controlled trials evaluating bland transarterial embolization (TAE), conventional TACE, drug-eluting bead chemoembolization (DEB-TACE), or transarterial radioembolization (TARE), either alone or combined with adjuvant chemotherapy, or local liver ablation, or external radiotherapy for unresectable HCC up to June 2017. Random effects Bayesian models with a binomial and normal likelihood were fitted (WinBUGS). Primary endpoint was patient survival expressed as hazard ratios (HR) and 95% credible intervals. An exponential model was used to fit patient survival curves. Safety and objective response were calculated as odds ratios (OR) and accompanying 95% credible intervals. Competing treatments were ranked with the SUCRA statistic. Heterogeneity-adjusted effective sample sizes were calculated to evaluate information size for each comparison. Quality of evidence (QoE) was assessed with the GRADE system adapted for NMA reports. All analyses complied with the ISPOR-AMCP-NCP Task Force Report for good practice in NMA.

FINDINGS

The network of evidence included 55 RCTs (12 direct comparisons) with 5,763 patients with preserved liver function and unresectable HCC (intermediate to advanced stage). All embolization strategies achieved a significant survival gain over control treatment (HR range, 0.42-0.76; very low-to-moderate QoE). However, TACE, DEB-TACE, TARE and adjuvant systemic agents did not confer any survival benefit over bland TAE alone (moderate QoE, except low in case of TARE). There was moderate QoE that TACE combined with external radiation or liver ablation achieved the best patient survival (SUCRA 86% and 96%, respectively). Estimated median survival was 13.9 months in control, 18.1 months in TACE, 20.6 months with DEB-TACE, 20.8 months with bland TAE, 30.1 months in TACE plus external radiotherapy, and 33.3 months in TACE plus liver ablation. TARE was the safest treatment (SUCRA 77%), however, all examined therapies were associated with a significantly higher risk of toxicity over control (OR range, 6.35 to 68.5). TACE, DEB-TACE, TARE and adjuvant systemic agents did not improve objective response over bland embolization alone (OR range, 0.85 to 1.65). There was clinical diversity among included randomized controlled trials, but statistical heterogeneity was low.

CONCLUSIONS

Chemo- and radio-embolization for unresectable hepatocellular carcinoma may improve tumour objective response and patient survival, but are not more effective than bland particle embolization. Chemoembolization combined with external radiotherapy or local liver ablation may significantly improve tumour response and patient survival rates over embolization monotherapies. Quality of evidence remains mostly low to moderate because of clinical diversity.

SYSTEMATIC REVIEW REGISTRATION

CRD42016035796 (http://www.crd.york.ac.uk/PROSPERO).

Predictive values of serum VEGF and CRP levels combined with contrast enhanced MRI in hepatocellular carcinoma patients after TACE

This study explored the predictive value of serum vascular endothelial growth factor (VEGF) and C-reactive protein (CRP) levels combined with enhanced magnetic resonance imaging (MRI) in hepatocellular carcinoma (HCC) patients after transcatheter arterial chemoembolization (TACE). One hundred and seventeen patients who received TACE from June 2010 to December 2012 in our hospital were included in this study. Serum VEGF and CRP levels before and after TACE were determined by ELISA and single immunodiffusion method for analyzing the association of serum levels with pathological features. Enhanced MRI was utilized before and after TACE to measure tumor size and ADC value in enhanced region and non-enhanced region. MRI data were combined with serum VEGF and CRP levels to analyze the predictive value in efficacy and prognosis for HCC patients after TACE. The serum VEGF and CRP levels after TACE were increased, but can return to normal levels in a certain time. VEGF and CRP levels were not statistically associated with tumor location, tumor staining or presence of membrane (all P > 0.05), but closely correlated with combined portal vein tumor thrombus, combined arteriovenous fistula and distant metastasis (all P < 0.05). Low levels of serum VEGF and CRP, small tumor size and low ADC value before treatment indicated a better prognosis. The sensitivity and specificity of serum VEGF and CRP levels, tumor size and ADC value were respectively 92.31% and 88.46%, 93.85% and 90.38%, 81.54% and 78.85% as well as 47.69% and 84.62%. Serum VEGF and CRP levels, tumor size and ADC value could predict the efficacy of TACE for HCC patients. Serum VEGF and CRP levels combined with enhanced MRI may serve as markers for efficacy and prognosis evaluation in HCC patients after TACE.

Sulfamethazine-based pH-sensitive hydrogels with potential application for transcatheter arterial chemoembolization therapy

Transcatheter arterial chemoembolization (TACE) is the most common palliative therapy for unresectable hepatocellular carcinoma (HCC). The conventional TACE technique, which employs the Lipiodol® emulsion, has been widely used for human cancer treatments. However, this delivery system seems to be inconsistent and unstable in maintaining a high concentration of drugs at tumor sites. An alternative approach for TACE is loading drugs into a liquid embolic solution that exists as an injectable solution and can exhibit a sol-to-gel phase transition to form a solidified state once delivered to the tumor site. Here, we develop a novel sulfamethazine-based anionic pH-sensitive block copolymer with potential application as a radiopaque embolic material. The copolymer, named PCL-PEG-SM, and comprised of poly(ε-caprolactone), sulfamethazine, and poly(ethylene glycol), was fabricated by free radical polymerization. An aqueous solution of the developed copolymer underwent a sol-to-gel phase transition upon lowering the environmental pH to create a gel region that covered the physiological condition (pH 7.4, 37°C) and the low pH conditions at tumor sites (pH 6.5-7.0, 37°C). The release of doxorubicin (DOX) from DOX-loaded copolymer hydrogels could be sustained for more than 4weeks in vitro, and the released DOX retained its fully bioactivity via inhibition the proliferation of hepatic cancer cells. The radiopaque embolic formulations that were prepared by mixing copolymer solutions at pH 8.0 with Lipiodol®, a long-lasting X-ray contrast agent, could exhibit the gelation inside the tumor after intratumoral injection or intraarterial administration using a VX2 carcinoma hepatic tumor rabbit model. These results suggest that a novel anionic pH-sensitive copolymer has been developed with a potential application as a liquid radiopaque embolic solution for TACE of HCC.

STATE OF SIGNIFICANCE

Transcatheter arterial chemoembolization (TACE) has been widely used as a palliative treatment therapy for unresectable hepatocellular carcinoma (HCC). Conventional TACE technique, which usually employs emulsion of DOX-in-Lipiodol®, followed by an embolic agent, has significant limitation of inconsistency and lack of controlled release ability. To address these limitations of conventional TACE material system, we introduced a novel liquid radiopaque embolic material from our pH-sensitive hydrogel. The material has low viscosity that can be injected via a microcatheter, rather biocompatibility, and drug controlled release ability. Importantly, it can form gel in the tumor as well as tumoral vasculature in response to the lowered pH at the tumor site, which proved the potential for the use to treat HCC by TACE therapy.

Distribution of Iron Oxide Core-Titanium Dioxide Shell Nanoparticles in VX2 Tumor Bearing Rabbits Introduced by Two Different Delivery Modalities

This work compares intravenous (IV) versus fluoroscopy-guided transarterial intra-catheter (IC) delivery of iron oxide core-titanium dioxide shell nanoparticles (NPs) in vivo in VX2 model of liver cancer in rabbits. NPs coated with glucose and decorated with a peptide sequence from cortactin were administered to animals with developed VX2 liver cancer. Two hours after NPs delivery tumors, normal liver, kidney, lung and spleen tissues were harvested and used for a series on histological and elemental analysis tests. Quantification of NPs in tissues was done both by bulk inductively coupled plasma mass spectrometry (ICP-MS) analysis and by hard X-ray fluorescence microscopy. Both IV and IC NPs injection are feasible modalities for delivering NPs to VX2 liver tumors with comparable tumor accumulation. It is possible that this is an outcome of the fact that VX2 tumors are highly vascularized and hemorrhagic, and therefore enhanced permeability and retention (EPR) plays the most significant role in accumulation of nanoparticles in tumor tissue. It is, however, interesting to note that IV delivery led to increased sequestration of NPs by spleen and normal liver tissue, while IC delivery lead to more NP positive Kupffer cells. This difference is most likely a direct outcome of blood flow dynamics. Armed with this knowledge about nanoparticle delivery, we plan to test them as radiosensitizers in the future.

GALNT14 genotype effectively predicts the therapeutic response in unresectable hepatocellular carcinoma treated with transcatheter arterial chemoembolization

Aim: Transcatheter arterial chemoembolization is currently the standard treatment in hepatocellular carcinoma patients with Barcelona Clinic Liver Cancer stage B. Genomic variants of GALNT14 were recently identified as effective predictors for chemotherapy responses in Barcelona Clinic Liver Cancer stage C patients. Methods: We investigated the prognosis predictive value of GALNT14 genotypes in 327 hepatocelluar carcinoma patients treated by transcatheter arterial chemoembolization. Result: Cox proportional hazards model analysis showed that the genotype ‘TT’ was associated with shorter time-to-response (multivariate p < 0.001), time-to-complete-response (p = 0.004) and longer time-to-tumor progression (p < 0.001), compared with the genotype ‘non-TT’. In patients with albumin <3.5 g/dl, genotype ‘TT’ was associated with longer overall survival (p = 0.027). Finally, genotype ‘TT’ correlated with higher cancer-to-noncancer ratios of GALNT14 protein levels, lower cancer-to-noncancer ratios of antiapoptotic cFLIP-S, and a clustered glycosylation pattern in the extracellular domain of death receptor 5. Conclusion: GALNT14 genotypes were significantly associated with clinical outcomes of transcatheter arterial chemoembolization. The differential status of extrinsic apoptotic signaling between cancerous and non-cancerous tissues might underlie the clinical association.

The Changes of HIF-1α and VEGF Expression After TACE in Patients With Hepatocellular Carcinoma

As a common malignant tumor, hepatocellular carcinoma (HCC) has a high prevalence and is a serious threat to human health. The surgical resection rate of HCC is low, and the prognosis is poor. Although transarterial chemoembolization (TACE) is the main treatment for HCC patients who are not candidates for surgical resection, it is not considered a curative procedure. For HCC, poor TACE efficacy or TACE failure may be related to tumor angiogenesis of the residual disease. Among the many regulatory factors in tumor angiogenesis, hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) play vital roles in this process. In this paper, we conducted a review of the dynamic change and relevance of HIF-1α and VEGF levels after TACE of HCC patients.

A novel sulfamethazine-based pH-sensitive copolymer for injectable radiopaque embolic hydrogels with potential application in hepatocellular carcinoma therapy

After transcatheter delivery through hepatic artery, a hydrogel can be formed within tumor vasculature by the decrease of environmental pH, block the blood vessel and control the release of loaded anticancer drugs.

Guide for diagnosis and treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is ranked as the 5^th common type of cancer worldwide and is considered as the 3^rd common reason for cancer-related deaths. HCC often occurs on top of a cirrhotic liver. The prognosis is determined by several factors; tumour extension, alpha-fetoprotein (AFP) concentration, histologic subtype of the tumour, degree of liver dysfunction, and the patient’s performance status. HCC prognosis is strongly correlated with diagnostic delay. To date, no ideal screening modality has been developed. Analysis of recent studies showed that AFP assessment lacks adequate sensitivity and specificity for effective surveillance and diagnosis. Many tumour markers have been tested in clinical trials without progressing to routine use in clinical practice. Thus, surveillance is still based on ultrasound (US) examination every 6 mo. Imaging studies for diagnosis of HCC can fall into one of two main categories: routine non-invasive studies such as US, computed tomography (CT), and magnetic resonance imaging, and more specialized invasive techniques including CT during hepatic arteriography and CT arterial portography in addition to the conventional hepatic angiography. This article provides an overview and spotlight on the different diagnostic modalities and treatment options of HCC.