New intra-arterial drug delivery system for the treatment of liver cancer: preclinical assessment in a rabbit model of liver cancer

The Recent Trends of Systemic Treatments and Locoregional Therapies for Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a hepatic malignancy that has a rapidly increasing incidence. CCA is anatomically classified into intrahepatic (iCCA) and extrahepatic (eCCA), which is further divided into perihilar (pCCA) and distal (dCCA) subtypes, with higher incidence rates in Asia. Despite its rarity, CCA has a low 5-year survival rate and remains the leading cause of primary liver tumor-related death over the past 10-20 years. The systemic therapy section discusses gemcitabine-based regimens as primary treatments, along with oxaliplatin-based options. Second-line therapy is limited but may include short-term infusional fluorouracil (FU) plus leucovorin (LV) and oxaliplatin. The adjuvant therapy section discusses approaches to improve overall survival (OS) post-surgery. However, only a minority of CCA patients qualify for surgical resection. In comparison to adjuvant therapies, neoadjuvant therapy for unresectable cases shows promise. Gemcitabine and cisplatin indicate potential benefits for patients awaiting liver transplantation. The addition of immunotherapies to chemotherapy in combination is discussed. Nivolumab and innovative approaches like CAR-T cells, TRBAs, and oncolytic viruses are explored. We aim in this review to provide a comprehensive report on the systemic and locoregional therapies for CCA.

Comparison of efficacy and safety of conventional transarterial chemoembolization and drug-eluting bead transarterial chemoembolization in unresectable intrahepatic cholangiocarcinoma: A multicenter retrospective cohort study

PURPOSE

The efficacy and safety of drug-eluting bead transarterial chemoembolization (DEB-TACE) and conventional TACE (c-TACE) in the treatment of patients with unresectable intrahepatic cholangiocarcinoma (ICC) remained controversial. Therefore, we aimed to compare the efficacy and safety between c-TACE and DEB-TACE among patients with ICC.

METHOD

Between June 10, 2016 and November 19, 2022, consecutive patients with pathological diagnoses of ICC were divided into the DEB-TACE group and the c-TACE group based on the type of TACE treatment they received. The Kaplan-Meier method and log-rank test were used to compare overall survival (OS) between the two groups. Propensity score matching (PSM) was used to balance the characteristics between the c-TACE group and the DEB-TACE group.

RESULTS

A total of 132 patients were included in this study, with 64 patients in the c-TACE group and 68 patients in the DEB-TACE group. The median OS for c-TACE and DEB-TACE was 5 and 12 months, respectively. The objective response rate (ORR) for c-TACE and DEB-TACE was 0 % and 66.2 %, respectively; the disease control rate (DCR) was 37.5 % and 91.2 %. There were no significant differences between c-TACE and DEB-TACE among adverse effects at 3 months after treatment (P > 0.05). The results remained consistent after PSM. The Cox regression demonstrated that the DEB-TACE was an independent protective factor for OS.

CONCLUSIONS

Patients in the DEB-TACE group had longer OS and higher ORR and DCR than those in the c-TACE group, but no significant difference was observed between the two groups regarding adverse effects.

Discussing the safety and effectiveness of transcatheter arterial embolization combined with intravenous chemotherapy in treating locally advanced breast cancer

To investigate the efficacy and safety of drug-eluting bead-transarterial chemoembolization (DEB-TACE) combined with systemic chemotherapy in HR+/Her2- locally advanced breast cancer (LABC) patients. A controlled study was conducted on LABC patients treated at Jianyang People's Hospital and the First Affiliated Hospital of Chengdu Medical College from December 2020 to June 2022. The patients were randomly divided into the experimental group and the control group. The experimental group received DEB-TACE combined with the TAC regimen (175 mg/m2 paclitaxel-loaded albumin, 50 mg/m2 Doxorubicin, and 500 mg/m2 cyclophosphamide), while the control group received the TAC regimen intravenously. The therapeutic efficacy was evaluated using the mRECIST criteria. Statistical analysis was performed using SPSS 22.0 software, and baseline characteristics, overall response rate (ORR), pathological complete response (PCR), adverse reactions, and complications were compared between the two groups using paired t-test and chi-square test. A total of 60 patients were included, with 30 patients in the experimental group (50%) and 30 patients in the control group (50%). After the first treatment, the ORR was 90% in the experimental group and 60% in the control group (P < 0.05). The overall ORR was 100% in the experimental group and 83% in the control group (P < 0.05). PCR was achieved in 14 patients (47%) in the experimental group and 4 patients (13%) in the control group. The main adverse reactions in the experimental group were skin blistering, pigmentation, and pain. There was no statistically significant difference in vomiting and grade II or above bone marrow suppression between the two groups. No grade III or above adverse events occurred in either group. The comparison of tumor shrinkage between the two groups was P = 0.051, and axillary lymph node shrinkage was P < 0.05. The use of drug-eluting beads in combination with neoadjuvant chemotherapy is a feasible and safe treatment option for locally advanced breast cancer patients.

A Comparative Study of DC Beads, Callispheres and Multimodal Imaging Nano-Assembled Microspheres Loaded with Irinotecan in Vitro

Introduction: In recent years, the development of drug-eluting embolization beads that can be imaged has become a hot research topic in regard to meeting clinical needs. In our previous study, we successfully developed nano-assembled microspheres (NAMs) for multimodal imaging purposes. NAMs can not only be visualized under CT/MR/Raman imaging but can also load clinically required doses of doxorubicin. It is important to systematically compare the pharmacokinetics of NAMs with those of commercially available DC Beads and CalliSpheres to evaluate the clinical application potential of NAMs. Methods: In our study, we compared NAMs with two types of drug-eluting beads (DEBs) in terms of irinotecan, drug-loading capacity, release profiles, microsphere diameter variation, and morphological characteristics. Results: Our results indicate that NAMs had an irinotecan loading capacity similar to those of DC Beads and CalliSpheres but exhibited better sustained release in vitro. Conclusion: NAMs have great potential for application in transcatheter arterial chemoembolization for the treatment of colorectal cancer liver metastases.

Effects of HepaSphere microsphere encapsule epirubicin with a new loading method transarterial chemoembolization: in vitro and in vivo experiments

METHODS

HS microspheres were loaded in a solution of hypertonic saline and contrast medium at different ratios. Morphology, size distribution, and drug loading capacity of the microsphere were evaluated. Rabbits with hepatic VX2 tumors underwent conventional TACE, drug-eluting beads TACE with HS microsphere loading epirubicin by recommended method (dTACE) or a new loading method (ndTACE). The plasma and tissue epirubicin concentration, tumor necrosis, and the microsphere distribution within the tumor were assessed.

RESULTS

It was found that the mean diameter of HS microspheres was effectively reduced to 102 ± 14 μm after loading with 10.0% NaCl and Ultravist (370 mg I /mL) at a ratio of 2: 8 ml. The loading capacity reached 78.7%. It was noted that the concentration of tumor epirubicin was significantly higher (p = 0.016) in the ndTACE group (11,989.8 ± 5776.6 ng/g) than the concentration in the dTACE (6516.5 ± 3682.3 ng/g) and in cTACE groups (1564.1 ± 696.1 ng/g, p < 0.001). Further, the tumor necrosis in group with the new loading method (ndTACE) was 92.4%.

CONCLUSIONS

The size of HS microsphere can be effectively reduced when it is loaded with a mixture of hypertonic saline and non-ionic contrast material. HS microsphere loaded with epirubicin using the new method (ndTACE) can increase the drug concentration in tumor and hence exert better improved antitumor effect.

Drug-Eluting Bead Transarterial Chemoembolization Versus Radiofrequency Ablation as an Initial Treatment of Single Small (≤ 3 cm) Hepatocellular Carcinoma

BACKGROUND

In this study, we aimed to compare the long-term therapeutic outcomes of drug-eluting bead transarterial chemoembolization (DEB-TACE) with those of radiofrequency ablation (RFA) for the initial treatment of a single small (≤ 3 cm) hepatocellular carcinoma (HCC).

METHODS

From January 2010 to December 2021, 259 consecutive patients who underwent DEB-TACE (67 patients) or RFA (192 patients) as a first-line treatment for a single small HCC were enrolled in this retrospective study. The therapeutic outcomes, including cumulative intrahepatic local tumor progression (LTP), progression-free survival (PFS), and long-term overall survival (OS) rates, were compared between the two groups before and after propensity score (PS) matching. Multivariate Cox proportional hazard models were used to evaluate the prognostic factors and differences in OS and PFS between the two groups for all 92 patients after PS matching.

RESULTS

After PS matching, the 1-, 2-, 3-, and 5-year LTP rates were lower in the RFA group than those in the DEB-TACE group (P < 0.001), and the 1-, 2-, 3-, and 5-year PFS rates in the RFA group were higher than those in the DEB-TACE group (P = 0.007). However, the 1-, 2-, 3-, and 5-year OS rates were not significantly different between the RFA and DEB-TACE groups (P = 0.584). Moreover, the OS was not significantly different between the RFA and DEB-TACE groups in the univariate and multivariate analyses, with a hazard ratio (HR) of 0.81. The PFS was significantly higher in the RFA group than that in the DEB-TACE group in the univariate analyses, with a HR of 0.44 (P = 0.009). Multivariate Cox regression analysis showed that albumin (P = 0.019) was an independent prognostic factor for OS. Additionally, the major complication rates were not significantly different between the DEB-TACE and RFA groups (P = 1.000).

CONCLUSION

The LTP and PFS rates of RFA were superior to those of DEB-TACE in the initial treatment of single small HCC after PS matching. However, the OS rates were not significantly different between RFA and DEB-TACE. Therefore, DEB-TACE may be considered an efficient substitute for RFA in some patients with a single small HCC who are ineligible for RFA.

Current progress of pig models for liver cancer research

Preclinical trials play critical roles in assessing the safety and efficiency of novel therapeutic strategies for human diseases including live cancer. However, most therapeutic strategies that were proved to be effective in preclinical cancer models failed in human clinical trials due to the lack of appropriate disease animal models. Therefore, it is of importance and urgent to develop a precise animal model for preclinical cancer research. Liver cancer is one of the most frequently diagnosed cancers with low 5-year survival rate. Recently, porcine attracted increasing attentions as animal model in biomedical research. Porcine liver cancer model may provide a promising platform for biomedical research due to their similarities to human being in body size, anatomical characteristics, physiology and pathophysiology. In this review, we comprehensively summarized and discussed the advantages and disadvantages, rationale, current status and progress of pig models for liver cancer research.

Drug-eluting beads versus conventional transarterial chemoembolization for the treatment of unresectable hepatocellular carcinoma: A meta-analysis

BACKGROUND

Transarterial chemoembolization (TACE) consists of conventional TACE (cTACE) and drug-eluting beads TACE (DEB-TACE). The benefits of the 2 treatments remain controversial. We conduct this meta-analysis to assess the efficacy and safety of the 2 methods for the patients with unresectable hepatocellular carcinoma.

METHODS

In order to get a sound conclusion, we did thorough search all relevant studies with clear and stringent keyword criteria on the main databases. Objective tumor response rate, overall survival (OS) rate and adverse events were calculated and analyzed by RevMan 5.3 software. The random-effects or fixed-effects model was applied to pool the estimates according to Cochran Q test and I2 statistics.

RESULTS

Twenty-four studies involving 2987 patients were eligible. DEB-TACE significantly improved objective tumor response rate (OR) (risk ratio [RR] = 1.27, 95% confidence interval [CI] [1.08, 1.48]; P = .003). While as for 1-year, 2-year, 3-year, 5-year OS rates, there were no evidences to indicate that DEB-TACE was significantly better than cTACE (RR = 1.05, 95% CI [0.99, 1.11]; P = .08), (RR = 1.02, 95% CI [0.93, 1.11]; P = .68), (RR = 0.92, 95% CI [0.77, 1.10]; P = .37), (RR = 0.92, 95% CI [0.47, 1.80]; P = .81), respectively. Adverse events rate (AE) was also similar in both groups (RR = 1.11, 95% CI [0.99,1.26]; P = .08).

CONCLUSION

This meta-analysis demonstrates that DEB-TACE is not superior than cTACE regarding to OS and AE. However, DEB-TACE still be considered to provide a better objective tumor response rate for patients with unresectable hepatocellular carcinoma.

Advanced therapeutics avenues in hepatocellular carcinoma: a novel paradigm

Hepatocellular carcinoma (HCC) is the most frequent type of primary liver cancer, and it poses a significant risk to patients health and longevity due to its high morbidity and fatality rates. Surgical ablation, radiotherapy, chemotherapy, and, most recently, immunotherapy have all been investigated for HCC, but none have yielded the desired outcomes. Several unique nanocarrier drug delivery techniques have been studied for their potential therapeutic implications in the treatment of HCC. Nanoparticle-based imaging could be effective for more accurate HCC diagnosis. Since its inception, nanomedicine has significantly transformed the approach to both the treatment and diagnostics of liver cancer. Nanoparticles (NPs) are being studied as a potential treatment for liver cancer because of their ability to carry small substances, such as treatment with chemotherapy, microRNA, and therapeutic genes. The primary focus of this study is on the most current discoveries and practical uses of nanomedicine-based diagnostic and therapeutic techniques for liver cancer. In this section, we had gone over what we know about metabolic dysfunction in HCC and the treatment options that attempt to fix it by targeting metabolic pathways. Furthermore, we propose a multi-target metabolic strategy as a viable HCC treatment option. Based on the findings given here, the scientists believe that smart nanomaterials have great promise for improving cancer theranostics and opening up new avenues for tumor diagnosis and treatment.

Multidisciplinary Taiwan consensus for the use of conventional TACE in hepatocellular carcinoma treatment

Developed in early 1980s, transarterial chemoembolization (TACE) with Lipiodol was adopted globally after large-scale randomized control trials and meta-analyses proving its effectiveness were completed. Also known as "conventional TACE" (cTACE), TACE is currently the first-line treatment for patients with unresectable intermediate stage hepatocellular carcinoma (HCC) and delivers both ischemic and cytotoxic effects to targeted tumors. Although new technology and clinical studies have contributed to a more comprehensive understanding of when and how to apply this widely-adopted therapeutic modality, some of these new findings and techniques have yet to be incorporated into a guideline appropriate for Taiwan. In addition, differences in the underlying liver pathologies and treatment practices for transcatheter embolization between Taiwan and other Asian or Western populations have not been adequately addressed, with significant variations in the cTACE protocols adopted in different parts of the world. These mainly revolve around the amount and type of chemotherapeutic agents used, the type of embolic materials, reliance on Lipiodol, and the degree of selectiveness in catheter positioning. Subsequently, interpreting and comparing results obtained from different centers in a systematic fashion remain difficult, even for experienced practitioners. To address these concerns, we convened a panel of experts specializing in different aspects of HCC treatment to devise modernized recommendations that reflect recent clinical experiences, as well as cTACE protocols which are tailored for use in Taiwan. The conclusions of this expert panel are described herein.

Drug-Eluting Embolic Loaded with Tyrosine Kinase Inhibitor Targeted Therapies for Transarterial Chemoembolization in a VX2 Model

Drug-eluting embolic transarterial chemoembolization (DEE-TACE) improves the overall survival of hepatocellular carcinoma (HCC), but the agents used are not tailored to HCC. Our patented liposomal formulation enables the loading and elution of targeted therapies onto DEEs. This study aimed to establish the safety, feasibility, and pharmacokinetics of sorafenib or regorafenib DEE-TACE in a VX2 model. DEE-TACE was performed in VX2 hepatic tumors in a selective manner until stasis using liposomal sorafenib- or regorafenib-loaded DEEs. The animals were euthanized at 1, 24, and 72 h timepoints post embolization. Blood samples were taken for pharmacokinetics at 5 and 20 min and at 1, 24, and 72 h. Measurements of sorafenib or regorafenib were performed in all tissue samples on explanted hepatic tissue using the same mass spectrometry method. Histopathological examinations were carried out on tumor tissues and non-embolized hepatic specimens. DEE-TACE was performed on 23 rabbits. The plasma concentrations of sorafenib and regorafenib were statistically significantly several folds lower than the embolized liver at all examined timepoints. This study demonstrates the feasibility of loading sorafenib or regorafenib onto commercially available DEEs for use in TACE. The drugs eluted locally without release into systemic circulation.

Use of doxorubicin-eluting bead transarterial chemoembolization for unresectable hepatocellular carcinoma with portal vein invasion: a prospective study

Background/Aim

To evaluate the applicability of transarterial chemoembolization (TACE) treatment with doxorubicin drug-eluting beads (DEBs) in advanced hepatocellular carcinoma (HCC) patients with portal vein invasion (PVI).

Methods

This prospective study was approved by the institutional review board and informed consent was obtained from all participants. A total of 30 HCC patients with PVI received DEB-TACE between 2015 and 2018. The following parameters were evaluated: complications during DEB-TACE, abdominal pain, fever, and laboratory outcomes, including liver function change. Overall survival (OS), time to progression (TTP), and adverse events were also analyzed and assessed.

Results

DEBs measuring 100-300 μm in diameter were loaded with doxorubicin (150 mg per procedure). There were no complications during DEB-TACE and no significant differences in the levels of prothrombin time, serum albumin, or total bilirubin at follow-up compared to baseline. The median TTP was 102 days (95% confidence interval [CI], 42-207 days) and the median OS was 216 days (95% CI, 160-336 days). Three patients (10%) had severe adverse reactions, including transient acute cholangitis (n=1), cerebellar infarction (n=1), and pulmonary embolism (n=1), but no treatment-related death occurred.

Conclusions

DEB-TACE may be a therapeutic option for advanced HCC patients with PVI.

Clinical strategy of conversion therapy and surgical treatment for liver metastases from colorectal cancer

Colorectal cancer is one of the common malignant tumors of the digestive system in clinical practice. Due to the anatomical characteristics of the colorectum itself, colorectal cancer is prone to liver metastasis. Approximately 15%-25% of colorectal cancer cases are complicated with liver metastasis at diagnosis, 15%-25% are complicated with liver metastasis after radical resection of colorectal cancer, and 80%-90% with liver metastasis cannot undergo radical resection initially. The 5-year survival rate is less than 5%, and liver metastasis is the main cause of death in patients with colorectal cancer. In recent years, with the clinical application of effective chemotherapy and molecular targeted drugs, as well as the rapid development of surgical techniques, an individualized safe, efficient, fast, treatment plan can be formulated according to patients' age, primary colorectal tumor location, degree of differentiation, Ras and B-Raf gene status, tumor size, number and distribution of metastases in the liver. By shrinking the tumor volume in the liver and increasing the residual liver volume, liver metastatic tumors can undergo surgical resection or disease-free status can be achieved in patients with liver metastasis. As a result, patients with colorectal liver metastases can achieve a 5-year survival rate of 30%-57%, which greatly improves the prognosis after operation. According to the postoperative adverse factors, individualized preventive measures are worked out to reduce the impact of adverse factors and improve the prognosis of patients with colorectal liver metastases. In this paper, we systematically discuss the clinical strategy of conversion therapy and surgical treatment for unresectable colorectal cancer liver metastases by reviewing the relevant domestic and foreign literature, so as to provide a theoretical reference for the selection of clinical treatment and program for patients with unresectable colorectal cancer liver metastases.

Selective Intra-Arterial Doxorubicin Eluting Microsphere Embolization for Desmoid Fibromatosis: A Combined Prospective and Retrospective Study

Simple Summary

Desmoid fibromatoses (DFs) are locally aggressive tumors composed of monoclonal fibroblasts within an abundant extracellular matrix. Systemic treatment with doxorubicin is effective, but associated with significant toxicity. We investigated arterial doxorubicin eluting embolization (DEE), an approach that delivers high doxorubicin concentrations to the tumor with limited systemic drug exposure, in 24 patients (median age, 24 years; interquartile range, 16–34). Most patients (71%) had one or more than one prior DFs treatment (surgery, systemic therapy, or both). Patients underwent a median of two (range, 1–4) DEE treatments, with a median of 49 mg (range, 8–75) doxorubicin per treatment. Efficacy outcomes were available for 23 patients. With a median follow-up of 8 months (interquartile range, 3–13), median tumor volumes decreased by 59% (interquartile range, 40–71%). Of 23 patients, 9 (39%), 12 (52%), and 2 (9%) had a partial response, stable disease, and progressive disease, respectively. The procedure was safe and well tolerated.

Abstract

Desmoid fibromatoses (DFs) are locally aggressive tumors composed of monoclonal fibroblasts within an abundant extracellular matrix. Systemic doxorubicin treatment is effective, but toxic. We investigated arterial doxorubicin eluting embolization (DEE), an approach characterized by high drug concentrations in the tumor alongside limited systemic drug exposure. The primary and secondary endpoints were radiological response using MRI and RECIST 1.1, respectively. The study included 24 patients (median age, 24; interquartile range, 16–34 years). Data were collected prospectively for 9 patients and retrospectively for 15 patients. The most frequent tumor locations were chest/abdomen wall and neck/shoulder/axilla (29% each). Of 24 patients, 7 (24%) were treatment naïve, and 17 (71%) had received one or two prior treatments. Patients underwent a median of two treatments (range, 1–4), with a median of 49 mg (range, 8–75) doxorubicin/treatment. Efficacy outcomes were available for 23 patients. With a median follow-up of 8 months (interquartile range, 3–13), median tumor volumes decreased by 59% (interquartile range, 40–71%) and T2 signal intensity decreased by 36% (interquartile range, 19–55%). Of 23 patients, 9 (39%), 12 (52%), and 2 (9%) had a partial response, stable disease, and progressive disease, respectively. DEE was safe and well tolerated, with one reported grade 3–4 adverse event (cord injury). In conclusion, DEE was safe and achieved rapid clinical/volumetric responses in DFs.

In vivo restoration of dystrophin expression in mdx mice using intra-muscular and intra-arterial injections of hydrogel microsphere carriers of exon skipping antisense oligonucleotides

Duchenne muscular dystrophy (DMD) is a genetic disease caused by a mutation in the X-linked Dytrophin gene preventing the expression of the functional protein. Exon skipping therapy using antisense oligonucleotides (AONs) is a promising therapeutic strategy for DMD. While benefits of AON therapy have been demonstrated, some challenges remain before this strategy can be applied more comprehensively to DMD patients. These include instability of AONs due to low nuclease resistance and poor tissue uptake. Delivery systems have been examined to improve the availability and stability of oligonucleotide drugs, including polymeric carriers. Previously, we showed the potential of a hydrogel-based polymeric carrier in the form of injectable PEG-fibrinogen (PF) microspheres for delivery of chemically modified 2'-O-methyl phosphorothioate (2OMePs) AONs. The PF microspheres proved to be cytocompatible and provided sustained release of the AONs for several weeks, causing increased cellular uptake in mdx dystrophic mouse cells. Here, we further investigated this delivery strategy by examining in vivo efficacy of this approach. The 2OMePS/PEI polyplexes loaded in PF microspheres were delivered by intramuscular (IM) or intra-femoral (IF) injections. We examined the carrier biodegradation profiles, AON uptake efficiency, dystrophin restoration, and muscle histopathology. Both administration routes enhanced dystrophin restoration and improved the histopathology of the mdx mice muscles. The IF administration of the microspheres improved the efficacy of the 2OMePS AONs over the IM administration. This was demonstrated by a higher exon skipping percentage and a smaller percentage of centered nucleus fibers (CNF) found in H&E-stained muscles. The restoration of dystrophin expression found for both IM and IF treatments revealed a reduced dystrophic phenotype of the treated muscles. The study concludes that injectable PF microspheres can be used as a carrier system to improve the overall therapeutic outcomes of exon skipping-based therapy for treating DMD.

Impact of Chemoembolic Regimen on Immune Cell Recruitment and Immune Checkpoint Marker Expression following Transcatheter Arterial Chemoembolization in a VX2 Rabbit Liver Tumor Model

PURPOSE

To characterize the effects of commonly used transcatheter arterial chemoembolization (TACE) regimens on the immune response and immune checkpoint marker expression using a VX2 rabbit liver tumor model.

MATERIALS AND METHODS

Twenty-four VX2 liver tumor-bearing New Zealand white rabbits were assigned to 7 groups (n = 3 per group) undergoing locoregional therapy as follows: (a) bicarbonate infusion without embolization, (b) conventional TACE (cTACE) using a water-in-oil emulsion containing doxorubicin mixed 1:2 with Lipiodol, drug-eluting embolic-TACE with either (c) idarubicin-eluting Oncozene microspheres (40 μm) or (d) doxorubicin-eluting Lumi beads (40-90 μm). For each therapy arm (b-d), a tandem set of 3 animals with additional bicarbonate infusion before TACE was added, to evaluate the effect of pH modification on the immune response. Three untreated rabbits served as controls. Tissue was harvested 24 hours after treatment, followed by digital immunohistochemistry quantification (counts/μm² ± SEM) of tumor-infiltrating cluster of differentiation 3⁺ T-lymphocytes, human leukocyte antigen DR type antigen-presenting cells (APCs), cytotoxic T-lymphocyte-associated protein-4 (CTLA-4), and programmed cell death protein-1 (PD-1)/PD-1 ligand (PD-L1) pathway axis expression.

RESULTS

Lumi-bead TACE induced significantly more intratumoral T-cell and APC infiltration than cTACE and Oncozene-microsphere TACE. Additionally, tumors treated with Lumi-bead TACE expressed significantly higher intratumoral immune checkpoint markers compared with cTACE and Oncozene-microsphere TACE. Neoadjuvant bicarbonate demonstrated the most pronounced effect on cTACE and resulted in a significant increase in intratumoral cluster of differentiation 3⁺ T-cell infiltration compared with cTACE alone.

CONCLUSIONS

This preclinical study revealed significant differences in evoked tumor immunogenicity depending on the choice of chemoembolic regimen for TACE.

Transarterial Chemoembolization Combined With Tyrosine Kinase Inhibitors for Intermediate-Stage Hepatocellular Carcinoma, What Else Can We Do?

Transarterial chemoembolization (TACE) has been considered the standard treatment for intermediate-stage hepatocellular carcinoma (HCC). However, intermediate‐stage HCC is highly heterogeneous with a broad population with varying tumour burdens, liver function. This suggests that TACE monotherapy treatment might not be suitable for all patients with intermediate‐stage HCC. The administration of tyrosine kinase inhibitors (TKIs) has become an important treatment option for improving the prognosis of patients with advanced HCC. Over the years, several trials have been conducted to explore the effects of TACE combined with TKIs for intermediate-stage HCC. However, the clinical efficacy is still controversial, and its potential clinical utility needs to be confirmed. This review will focus on the recent progress of TACE combined TKIs for intermediate-stage HCC.

Evaluation of immune-modulating drugs for use in drug-eluting microsphere transarterial embolization

Cancer immunotherapy has yet to reach its full potential due in part to limited response rates and side effects inherent to systemic delivery of immune-modulating drugs. Local administration of immunotherapy using drug-eluting embolic (DEE) microspheres as drug delivery vehicles for direct infusion into tumor-feeding arteries might increase and prolong tumor drug concentrations and reduce systemic drug exposure, potentially improving the risk-to-benefit ratio of these agents. The purpose of this study was to evaluate the ability of four immune modulators affecting two different immune pathways to potentiate replication of immune cells from a woodchuck model of hepatocellular carcinoma. DSR 6434, a Toll-like receptor agonist, and BMS-202, a PD-L1 checkpoint inhibitor, induced immune cell replication and were successfully loaded into radiopaque DEE microspheres in high concentrations. Release of DSR 6434 from the DEE microspheres was rapid (t99% = 0.4 h) upon submersion in a physiologic saline solution while BMS-202 demonstrated a more sustained release profile (t99% = 17.9 h). These findings demonstrate the feasibility of controlled delivery of immune-modulating drugs via a local DEE microsphere delivery paradigm.

Mechanisms of Pharmacoresistance in Hepatocellular Carcinoma: New Drugs but Old Problems

Hepatocellular carcinoma (HCC) is a malignancy with poor prognosis when diagnosed at advanced stages in which curative treatments are no longer applicable. A small group of these patients may still benefit from transarterial chemoembolization. The only therapeutic option for most patients with advanced HCC is systemic pharmacological treatments based on tyrosine kinase inhibitors (TKIs) and immunotherapy. Available drugs only slightly increase survival, as tumor cells possess additive and synergistic mechanisms of pharmacoresistance (MPRs) prior to or enhanced during treatment. Understanding the molecular basis of MPRs is crucial to elucidate the genetic signature underlying HCC resistome. This will permit the selection of biomarkers to predict drug treatment response and identify tumor weaknesses in a personalized and dynamic way. In this article, we have reviewed the role of MPRs in current first-line drugs and the combinations of immunotherapeutic agents with novel TKIs being tested in the treatment of advanced HCC.

Efficacy of Drug-Eluting Beads Transarterial Chemoembolization Plus Camrelizumab Compared With Conventional Transarterial Chemoembolization Plus Camrelizumab for Unresectable Hepatocellular Carcinoma

Objectives

The purpose of this study was to compare the efficacy and safety of drug-eluting beads transarterial chemoembolization plus camrelizumab (D-TACE-C) with conventional transarterial chemoembolization plus camrelizumab (C-TACE-C) in the treatment of patients with unresectable hepatocellular carcinoma (HCC).

Materials and Methods

This was a retrospective study that evaluated the consecutive medical records of patients with unresectable HCC who had undergone D-TACE-C or C-TACE-C from April 2020 to August 2021. Efficacy of treatment was evaluated using tumor response, progression-free survival (PFS) and survival rates. The adverse events were recorded.

Results

A total of 54 patients were included in this study, including 27 patients who had received D-TACE-C treatment, and 27 patients who had received C-TACE-C treatment. The median PFS and DCR in the D-TACE-C group were significantly longer than those for the C-TACE-C group (PFS: 10 vs. 3 months, P=.017; DCR: 70.4% vs. 40.7%, P = .028). Cox regression analysis showed that D-TACE-C was the only protective factor for PFS. The 6-month and 12-month survival rates in D-TACE-C group and C-TACE-C group were 85.2% versus 79.4% (P = .646) and 65.2% versus 65.1% (P = .903), respectively. Reactive cutaneous capillary endothelial proliferation was the most common adverse event associated with the treatment. There was no significant difference in the adverse events related to TACE and camrelizumab between the two groups. No treatment-related deaths occurred in this study.

Conclusions

D-TACE-C is a safe and well-tolerated treatment, and may produce better PFS and tumor response in patients with unresectable HCC than C-TACE-C.

Donafenib-Loaded Callispheres Beads Embolization in a VX2 Liver Tumor: Investigating Efficacy, Safety, and Improvement of Tumor Angiogenesis After Embolization

Objective

To investigate the efficiency and safety of callispheres beads loaded with donafenib (DCBs) for embolization in a VX2 liver tumor, as well as the improvement of tumor angiogenesis following embolization.

Methods

Forty New Zealand white rabbit VX2 liver tumors were treated with four different drugs via the hepatic artery: NS (normal saline), CB (blank callispheres beads), ACB (adriamycin-loaded callispheres beads) and DCB (DCBs). Hematoxylin-eosin staining was performed to assess tumor necrosis, while MRI was employed to detect the changes in tumor size. The safety was evaluated by the liver and kidney function parameters, and the immunofluorescence and immunohistochemical staining were performed to reflect the tumor hypoxia and tumor angiogenesis following embolization.

Results

The DCB group had the smallest tumor growth rate, but the tumor necrosis rate was the highest of the four groups. Compared to the CB and ACB groups, the DCB group did not aggravate the liver damage and had no influence on kidney function. The staining results showed that, although the tumor hypoxia deteriorated after DCBs embolization, the expression of VEGF (vascular endothelial growth factor) reduced, thus inhibiting tumor angiogenesis.

Conclusion

DCB administration via hepatic artery is an effective and safe treatment for a preclinical liver cancer model, with the unique benefit of suppressing tumor angiogenesis following embolization.

Comparison of tumor response following conventional versus drug-eluting bead transarterial chemoembolization in early- and very early-stage hepatocellular carcinoma

Objective

To compare the safety of conventional transarterial chemoembolization (cTACE) vs drug-eluting bead TACE (DEB-TACE) in very early- and early-stage hepatocellular carcinoma (HCC).

Methods

Data of patients with early- and very early-stage HCC treated with cTACE or DEB-TACE were evaluated retrospectively in this study. A total of 40 patients were included, 20 treated with cTACE and 20 with DEB-TACE. The cTACE and DEB-TACE groups were comprised of 80% and 75% males, while there were 20% females in cTACE group and 25% in Deb-TACE group respectively. The mean age of patients in cTACE group was 57.43 ​+ ​5.6 years, while it was 56.4 ​+ ​5.5 years in DEB-TACE group. All patients had liver status of Child–Pugh Class A and a score ≤ 7 in Child-Pugh class type B in very early- (stage 0) or early-phase (stage A) stages according to the Barcelona Clinic Liver Cancer (BCLC) system.

Results

The Child-Pugh class degradation in the cTACE group was slightly higher than that in the DEB-TACE group. Serious complications like peritumoral parenchymal ischemia were observed in 4 patients in the cTACE group and 5 in the DEB-TACE group. Localized bile duct dilation was seen in 2 patients in the cTACE group and 6 in the DEB-TACE group.

No significant variation in serious complications between the two groups was established in localized bile duct dilatation. Other minor complications noted were liver failure, liver abscess, liver infarction, acute cholecystitis, biliary tree necrosis, and mortality. Further, no substantial variation in tumor response between the groups was reported immediately and 1-year post-procedural assessment. Conversion rate to other treatment modalities such as surgical resection, radiofrequency ablation (RFA), or swap between cTACE and DEB-TACE was substantially higher in the DEB-TACE group (40%) than in the cTACE group (10%) at the 1-year completion period of the study.

Conclusion

In terms of tumor response, the DEB-TACE group showed a better response, to some extent, as an initial therapy for HCC in the early stages as compared to the cTACE group, and DEB-TACE also exhibited better clinical efficacy in patients with HCC.

CIRSE Standards of Practice on Hepatic Transarterial Chemoembolisation

This CIRSE Standards of Practice document is aimed at interventional radiologists and provides best practices for performing transarterial chemoembolisation. It has been developed by an expert writing group under the guidance of the CIRSE Standards of Practice Committee. It will encompass all technical details reflecting European practice of different TACE procedures (Lp-TACE, DEM-TACE, DSM-TACE, b-TACE) as well as revising the existing literature on the various clinical indications (HCC, mCRC, ICC, NET). Finally, new frontiers of development will also be discussed.

Vandetanib-eluting radiopaque beads for chemoembolization: physicochemical evaluation and biological activity of vandetanib in hypoxia

Vandetanib-eluting radiopaque beads (VERB) have been developed for use in transarterial chemoembolization of liver tumours, with the goal of combining embolization with local delivery of antiangiogenic therapy. The objective of this study was to investigate how embolization-induced hypoxia may affect antitumoural activity of vandetanib, an inhibitor of vascular endothelial growth factor receptor (VEGFR) and epidermal growth factor receptor (EGFR), in the context of hepatocellular carcinoma (HCC) treatment. We studied the effect of vandetanib on proliferation, cell cycle and apoptosis of HCC cells, in hypoxic conditions, as well as the direct effects of the beads on 3D HCC spheroids. Vandetanib suppressed proliferation and induced apoptosis of HCC cells in vitro and was equipotent in hypoxic and normoxic conditions. High degrees of apoptosis were observed among cell lines in which vandetanib suppressed ERK1/2 phosphorylation and upregulated the proapoptotic protein Bim, but this did not appear essential for vandetanib-induced cell death in all cell lines. Vandetanib also suppressed the hypoxia-induced secretion of VEGF from HCC cells and inhibited proliferation of endothelial cells. Incubation of tumour spheroids with VERB led to sustained growth inhibition equivalent to the effect of free drug. We conclude that vandetanib has both antiangiogenic and direct anticancer activity against HCC cells even in hypoxic conditions, warranting the further evaluation of VERB as novel anticancer agents.

Transcatheter Arterial Embolization Containing Donafenib Induces Anti-Angiogenesis and Tumoricidal CD8+ T-Cell Infiltration in Rabbit VX2 Liver Tumor

Purpose

To evaluate the effect and immune response of transcatheter arterial embolization (TAE) combined with donafenib in rabbit VX2 liver tumor model.

Materials and Methods

Thirty-six New Zealand white rabbits with VX2 liver tumor were randomly divided into three groups. The LD group was treated with the emulsion of 0.5 mL lipiodol and 4 mg donafenib via hepatic arterial administration. The LE group was treated with the emulsion of 0.5 mL lipiodol and 4 mg epirubicin. The control group was treated with the equal volume of saline. Four rabbits were euthanized in each group on day 1, 3 and 7 after treatment. The tumor growth, histological markers associated with angiogenesis and immune response were assessed by imaging and histopathology. In addition, immune modulatory cytokines included interleukin (IL)-6, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and biochemical hepatorenal function were measured.

Results

Compared to other groups, LD group achieved lower tumor growth rate, fewer metastatic lesions, and higher tumor necrosis rate on day 7 after treatment. The percentage of CD31-positive area in the LD group was significantly lower than that in the LE group on day 3 and 7 after treatment. In addition, CD8⁺ lymphocytes infiltration was more pronounced in LD group than in LE group on day 7 after treatment, regardless of in the tumor or adjacent liver tissue. Serum cytokines including IL-6, TNF-α and IFN-γ were strongly upregulated in the LD group on day 1 after treatment. And there was no significant difference in the hepatorenal function between LD group and LE group after treatment.

Conclusion

The combination of TAE and angiogenesis inhibitor donafenib resulted in a potentiated tumoricidal effect, anti-angiogenesis and antitumour T cell response in rabbit VX2 liver tumor model. This may provide a potential basis for exploring the immune-related mechanisms of embolization in liver cancer.

Transarterial chemoembolization using drug-eluting bead compared with radiofrequency ablation for treatment of single small hepatocellular carcinoma: a pilot non-randomized trial

Background/Aims

Surgical resection, transplantation, and radiofrequency ablation (RFA) are generally accepted as amenable treatments for small hepatocellular carcinoma (HCC). Recently drug-eluting beads (DEB) which had several treatment advantages were introduced for transarterial chemoembolization (TACE). The aim of this study was to evaluate feasibility and safety of DEB-TACE compared with RFA for the treatment of single small HCC.

Methods

In this pilot non-randomized trial, we assessed retrospective data of 40 patients who underwent DEB-TACE (n=21) or RFA (n=19) for single small (≤3 centimeter in greatest dimension) HCC. The primary outcomes were tumor response and time to recurrence. The secondary outcome was treatment-related complications.

Results

Complete response rate to DEB-TACE and RFA after first follow-up assessment was 90.5% and 94.7%, respectively (P=1.000). During mean follow-up of 87.6 months (95% confidence interval, 74.4-102), 7 patients experienced local recurrence. The 6- and 12-month cumulative local recurrence rate was 5.0% and 21.8% in DEB-TACE vs. 11.1% and 17.0% in RFA group (P=0.877). A total 14 distant intrahepatic recurrences were developed and 12- and 24-month cumulative distant intrahepatic recurrence rate was 20.6% and 42.7% in DEB-TACE vs. 17.2% and 36.3% in RFA group (P=0.844). Two patients experienced gangrenous cholecystitis after DEB-TACE requiring cholecystectomy as treatment-related adverse event.

Conclusions

Tumor response and recurrence rate after single session of DEB-TACE or RFA were similar. DEB-TACE could be applied selectively in patients with a single small HCC if the other therapeutic modality is unfeasible.

Magnetic mesoporous embolic microspheres in transcatheter arterial chemoembolization for liver cancer

Transcatheter arterial chemoembolization (TACE) is the main treatment for liver cancer. Although many embolic agents have been exploited in TACE, embolic agents combining embolization, drug loading, and imaging properties have not yet been constructed. Herein, we report a new magnetic mesoporous embolic microsphere that can simultaneously be loaded with doxorubicin (Dox), block vessels, and be observed by magnetic resonance imaging (MRI). The microspheres were prepared by decorating magnetic polystyrene/Fe₃O₄ particles with mesoporous organosilica microparticles (denoted as PS/Fe₃O₄@MONs). The PS/Fe₃O₄@MONs were uniformly spherical and large (50 µm), with a high specific surface area, uniform mesopores, and a Dox loading capacity of 460.8 µg mg^-1. Dox-loaded PS/Fe₃O₄@MONs (PS/Fe₃O₄@MON@Dox) effectively inhibited liver cancer cell growth. A VX2 rabbit liver tumor model was constructed to study the efficacy of TACE with PS/Fe₃O₄@MON@Dox. In vivo, PS/Fe₃O₄@MON@Dox could be smoothly delivered through an arterial catheter to achieve chemoembolization. Moreover, PS/Fe₃O₄@MON@Dox and residual tumor parenchyma could be distinguished on MRI, which is of great significance for evaluating the efficacy of TACE. Histopathology showed that PS/Fe₃O₄@MON@Dox could be deposited in the tumor vessels, completely blocking the blood supply. Overall, PS/Fe₃O₄@MON@Dox showed good drug loading, embolization and imaging performance as well as potential for use in TACE. STATEMENT OF SIGNIFICANCE: Transcatheter arterial chemoembolization (TACE) is the main treatment for liver cancer. Although many embolic agents have been exploited in TACE, embolic agents combining embolization, drug-loading, and imaging properties have not yet been constructed. In this work, we prepared magnetic mesoporous microspheres as a new embolic agent that can simultaneously load doxorubicin (Dox), block blood vessels and enable magnetic resonance imaging. Overall, this new embolic microsphere-mediated TACE strategy for liver cancer showed good therapeutic effects, and the PS/Fe₃O₄@MON@Dox embolic microspheres provide a new avenue for improving the efficacy of TACE for liver cancer and postoperative evaluation.

Interventional Treatment for Cholangiocarcinoma

Cholangiocarcinoma (CCA) is the second most common type of primary liver malignancy. The latest classification includes intrahepatic cholangiocarcinoma and extrahepatic cholangiocarcinoma, with the latter one further categorized into perihilar and distal cholangiocarcinoma. Although surgical resection is the preferred treatment for CCA, less than half of the patients are actually eligible for radical surgical resection. Interventional treatment, such as intra-arterial therapies, ablation, and brachytherapy (iodine-125 seed implantation), has become an acceptable palliative treatment for patients with unresectable CCA. For these patients, interventional treatment is helpful for locoregional control, symptom relief, and improving quality of life. Herein, in a timely and topical manner, we will review these advances and highlight future directions of research in this article.

Cell-Penetrating Peptides: Applications in Tumor Diagnosis and Therapeutics

Since their identification over twenty-five years ago, the plethora of cell-penetrating peptides (CPP) and their applications has skyrocketed. These 5 to 30 amino acid in length peptides have the unique property of breaching the cell membrane barrier while carrying cargoes larger than themselves into cells in an intact, functional form. CPPs can be conjugated to fluorophores, activatable probes, radioisotopes or contrast agents for imaging tissues, such as tumors. There is no singular mechanism for translocation of CPPs into a cell, and therefore, many CPPs are taken up by a multitude of cell types, creating the challenge of tumor-specific translocation and hindering clinical effectiveness. Varying strategies have been developed to combat this issue and enhance their diagnostic potential by derivatizing CPPs for better targeting by constructing specific cell-activated forms. These methods are currently being used to image integrin-expressing tumors, breast cancer cells, human histiocytic lymphoma and protease-secreting fibrosarcoma cells, to name a few. Additionally, identifying safe, effective therapeutics for malignant tumors has long been an active area of research. CPPs can circumvent many of the complications found in treating cancer with conventional therapeutics by targeted delivery of drugs into tumors, thereby decreasing off-target side effects, a feat not achievable by currently employed conventional chemotherapeutics. Myriad types of chemotherapeutics such as tyrosine kinase inhibitors, antitumor antibodies and nanoparticles can be functionally attached to these peptides, leading to the possibility of delivering established and novel cancer therapeutics directly to tumor tissue. While much research is needed to overcome potential issues with these peptides, they offer a significant advancement over current mechanisms to treat cancer. In this review, we present a brief overview of the research, leading to identification of CPPs with a comprehensive state-of-the-art review on the role of these novel peptides in both cancer diagnostics as well as therapeutics.

Prospective Multi-Center Korean Registry of Transcatheter Arterial Chemoembolization with Drug-Eluting Embolics for Nodular Hepatocellular Carcinoma: A Two-Year Outcome Analysis

Objective

To assess the two-year treatment outcomes of chemoembolization with drug-eluting embolics (DEE) for nodular hepatocellular carcinoma (HCC).

Materials and Methods

This study was a prospective, multicenter, registry-based, single-arm trial conducted at five university hospitals in Korea. Patients were recruited between May 2011 and April 2013, with a target population of 200. A DC Bead loaded with doxorubicin was used as the DEE agent. Patients were followed up for two years. Per-patient and per-lesion tumor response analysis, per-patient overall survival (OS) and progression-free survival (PFS) analysis, and per-lesion tumor control analysis were performed.

Results

The final study population included 152 patients, with 207 target lesions for the per-lesion analysis. At one-month, six-month, one-year, and two-year per-patient assessments, complete response (CR) rates were 40.1%, 43.0%, 33.3%, and 19.6%, respectively. The objective response (OR) rates were 91.4%, 55.4%, 35.1%, and 19.6%, respectively. The cumulative two-year OS rate was 79.7%. The cumulative two-year PFS rate was 22.4% and the median survival was 9.3 months. In multivariable analysis, the Child-Pugh score (p = 0.019) was an independent predictor of OS, and tumor multiplicity (p < 0.001), tumor size (p = 0.020), and Child-Pugh score (p = 0.006) were independent predictors of PFS. In per-lesion analysis, one-month, six-month, one-year and two-year CR rates were 57.5%, 58.5%, 45.2%, and 33.3%, respectively, and the OR rates were 84.1%, 65.2%, 46.6%, and 33.3%, respectively. The cumulative two-year per-lesion tumor control rate was 36.2%, and the median time was 14.1 months. The Child-Pugh score (p < 0.001) was the only independent predictor of tumor control. Serious adverse events were reported in 11 patients (7.2%).

Conclusion

DEE chemoembolization for nodular HCCs in the Korean population showed acceptable survival, tumor response, and safety profiles after a two-year follow-up. Good liver function (Child-Pugh score A5) was a key predictor of per-patient OS, PFS, and per-lesion tumor control.

Arsenic trioxide-loaded CalliSpheres: In vitro study of drug release and antitumor activity, and in vivo study of pharmacokinetics, treatment efficacy and safety in liver cancer

The aim of the present study was to investigate the arsenic trioxide (ATO) loading/releasing efficiency of CalliSphere beads (CBs), as well as the in vitro anticancer activity, in vivo pharmacokinetics, treatment efficacy and safety of ATO-eluting CBs in liver cancer. The ATO loading and releasing efficiencies in CBs were evaluated. Furthermore, cell viability, invasion, apoptosis, VEGF expression and MMP9 expression were determined in liver cancer cells treated with ATO-eluting CBs or ATO solution. Rabbit liver models were established and underwent TACE with ATO-eluting CBs or ATO/lipiodol emulsion. Subsequently, their ATO pharmacokinetics were determined and macroscopic/microscopic examinations were conducted. In vitro, CB-loaded ATO increased during 40 min with an optimal loading efficiency of 23.0±2.5%, and released ATO rapidly within the first 30 min (31.40±10.0%) then slowed down within the latter 48 h (47.20±4.70%). ATO-eluting CBs exhibited decreased cell viability to some extent and similar invasive cell count, apoptosis rate, VEGF and MMP9 levels compared with ATO solution at various concentrations and time-points. In vivo, ATO concentration was lower in plasma, but higher in tumor tissues, and necrosis was more complete in tumor tissue while milder in normal liver parenchyma after rabbit liver was embolized with ATO-eluting CBs compared with ATO/lipiodol emulsion. ATO-eluting CBs may be a novel and promising therapeutic option in treating liver cancer.

Oligometastatic Disease and Interventional Oncology: Rationale and Research Directions

Oligometastatic disease (OMD) is generally defined as a stage of clinically or radiographically demonstrated metastatic disease limited in total disease burden and without rapid spread. Interventional oncology performs local therapies for primary and metastatic cancers, including OMD. Interventional oncology treatments can be pursued both as definitive therapy and for palliative purposes. Applied to OMD, these interventions can offer patients a decreasing overall tumor burden, minimizing cancer morbidity, and early evidence suggests a survival benefit. Here, we discuss the range of interventional oncology treatments, including ablation, chemoembolization, radioembolization, and irreversible electroporation. We describe the rationale for their application to OMD and discuss future directions for research.

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.

Comparison of the efficacy and safety of conventional transarterial chemoembolization with and without drug-eluting beads embolization for the treatment of unresectable large hepatocellular carcinoma

AIM

Hepatocellular carcinoma (HCC) has a poor prognosis. Moreover, large HCCs have been commonly observed. We aimed to evaluate the efficacy and safety of drug-eluting beads transarterial chemoembolization (DEB-TACE) combined with conventional TACE (cTACE) for the treatment of patients with unresectable large HCCs (main tumor ≥5 cm in diameter) compared with cTACE alone.

METHODS

A retrospective matched cohort study was performed on consecutive patients with unresectable large HCCs who underwent TACE as the initial treatment at the Fujian Medical University Cancer Hospital from May 2017 and March 2019. Fifty-five patients who underwent DEB-TACE combined with cTACE were compared with a case-matched control group of 110 patients who received cTACE alone. We compared the tumor response at 1 and 3 months after TACE, time to progression (TTP), and adverse events between the groups.

RESULTS

The objective response rate was higher for the DEB-TACE combined with cTACE group than for the cTACE alone group at 1 (39 of 55 [70.9%] vs. 57 of 110 [51.8%], p = 0.019) and 3 months (27 of 43 [62.8%] vs. 31 of 71 [43.7%], p = 0.048) post-treatment. The DEB-TACE combined with cTACE group also had a significantly longer median TTP than that of the cTACE group (7.2 vs. 5.3 months, p = 0.039). Compared with the cTACE group, occurrences of abdominal pain, nausea/vomiting, and constipation were significantly more frequent in the DEB-TACE combined with cTACE group (p < 0.05).

CONCLUSION

Compared with cTACE alone, DEB-TACE combined with cTACE significantly increased the objective response rate at 1 and 3 months after the treatment of unresectable large HCCs, and had a longer TTP, without any significant increase in the number of severe complications.

Drug-eluting beads bronchial arterial chemoembolization plus intercostals arterial infusion chemotherapy is effective and well-tolerated in treating non-small cell lung cancer patients with refractory malignant pleural effusion

Background

The study aimed to explore the efficacy and safety of drug-eluting beads bronchial arterial chemoembolization (DEB-BACE) plus intercostals arterial infusion chemotherapy in non-small cell lung cancer (NSCLC) patients with refractory malignant pleural effusion (MPE).

Methods

17 NSCLC patients with refractory MPE treated by DEB-BACE plus the intercostals arterial infusion chemotherapy (DEB-BACE group) were recruited. Their treatment response [complete remission (CR), partial remission (PR), overall efficacy, failure] for MPE was assessed at 1 month after therapy; adverse effects were recorded; MPE progression-free survival and overall survival (OS) were calculated. Moreover, 19 NSCLC patients with refractory MPE treated by conventional chemotherapy were reviewed as control (chemotherapy group), then their medical records were collected.

Results

With respect to MPE response, DEB-BACE group exhibited increased CR (82.4% vs. 10.5%, P<0.001) and overall efficacy (100.0% vs. 52.6%, P=0.001), similar PR (17.6% vs. 42.1%, P=0.112) while less failure (0.0% vs. 47.4%, P=0.001) compared to chemotherapy group. Furthermore, OS was prolonged in DEB-BACE group (median: 13.4; 95% CI: 11.0–15.8 months) than chemotherapy group (median: 7.0; 95% CI: 4.4–9.6 months) (P=0.002). Further analyses displayed that in DEB-BACE group, CR was associated with improved ECOG score and longer MPE progression-free survival, and adverse events mainly included fever, chest distress/pain, gastrointestinal side effects, myelosuppression, rash and hemoptysis, which were all mild and tolerable.

Conclusions

DEB-BACE plus intercostals arterial infusion chemotherapy could serve as a salvage treatment option for NSCLC patients with refractory MPE.

Elastin-specific MRI of extracellular matrix-remodelling following hepatic radiofrequency-ablation in a VX2 liver tumor model

Hepatic radiofrequency ablation (RFA) induces a drastic alteration of the biomechanical environment in the peritumoral liver tissue. The resulting increase in matrix stiffness has been shown to significantly influence carcinogenesis and cancer progression after focal RF ablation. To investigate the potential of an elastin-specific MR agent (ESMA) for the assessment of extracellular matrix (ECM) remodeling in the periablational rim following RFA in a VX2 rabbit liver tumor-model, twelve New-Zealand-White-rabbits were implanted in the left liver lobe with VX2 tumor chunks from donor animals. RFA of tumors was performed using a perfused RF needle-applicator with a mean tip temperature of 70 °C. Animals were randomized into four groups for MR imaging and scanned at four different time points following RFA (week 0 [baseline], week 1, week 2 and week 3 after RFA), followed by sacrifice and histopathological analysis. ESMA-enhanced MR imaging was used to assess ECM remodeling. Gadobutrol was used as a third-space control agent. Molecular MR imaging using an elastin-specific probe demonstrated a progressive increase in contrast-to-noise ratio (CNR) (week 3: ESMA: 28.1 ± 6.0; gadobutrol: 3.5 ± 2.0), enabling non-invasive imaging of the peritumoral zone with high spatial-resolution, and accurate assessment of elastin deposition in the periablational rim. In vivo CNR correlated with ex vivo histomorphometry (ElasticaVanGiesson-stain, y = 1.2x - 1.8, R2 = 0.89, p < 0.05) and gadolinium concentrations at inductively coupled mass spectroscopy (ICP-MS, y = 0.04x + 1.2, R2 = 0.95, p < 0.05). Laser-ICP-MS confirmed colocalization of elastin-specific probe with elastic fibers. Following thermal ablation, molecular imaging using an elastin-specific MR probe is feasible and provides a quantifiable biomarker for the assessment of the ablation-induced remodeling of the ECM in the periablational rim.

Drug-eluting embolic microspheres: State-of-the-art and emerging clinical applications

INTRODUCTION

Drug-eluting embolic (DEE) microspheres, or drug-eluting beads (DEB), delivered by transarterial chemoembolization (TACE) serve as a therapeutic embolic to stop blood flow to tumors and a drug delivery vehicle. New combinations of drugs and DEE microspheres may exploit the potential synergy between mechanisms of drug activity and local tissue responses generated by TACE to enhance the efficacy of this mainstay therapy.

AREAS COVERED

This review provides an overview of key drug delivery concepts related to DEE microspheres with a focus on recent technological developments and promising emerging clinical applications as well as speculation into the future.

EXPERT OPINION

TACE has been performed for nearly four decades by injecting chemotherapy drugs into the arterial supply of tumors while simultaneously cutting off their blood supply, trying to starve and kill cancer cells, with varying degrees of success. The practice has evolved over the decades but has yet to fulfill the promise of truly personalized therapies envisioned through rational selection of drugs and real-time multi-parametric image guidance to target tumor clonality or heterogeneity. Recent technologic and pharmacologic developments have opened the door for potentially groundbreaking advances in how TACE with DEE microspheres is performed with the goal of achieving advancements that benefit patients.

Effect of Inhibiting Tumor Angiogenesis After Embolization in the Treatment of HCC with Apatinib-Loaded p(N-Isopropyl-Acrylamide-co-Butyl Methyl Acrylate) Temperature-Sensitive Nanogel

Background

Transcatheter arterial embolization (TAE) is widely used in hepatocellular carcinoma (HCC) therapy. Tumor hypoxia often correlates with the recurrence and metastasis of the tumor and is the critical factor limiting the treatment effect of TAE.

Purpose

To investigate the underlying mechanism and therapeutic potential of TAE combined with apatinib-loaded p(N-isopropyl-acrylamide-co-butyl methyl acrylate) temperature-sensitive (PIB) nanogel for the suppression of rabbit VX2 liver tumor growth.

Materials and Methods

Sixty-five VX2 tumor-burdened rabbits were randomly divided into five groups and treated transarterially with apatinib-loaded PIB (Group PA, 0.4 mL, n=13), PIB alone (Group P, 0.4 mL, n=13), iodized oil alone (Group I, 0.4 mL, n=13), apatinib solution (Group A, 0.4 mL, n=13) or saline (Group NS, 0.4 mL, n=13). The dose of apatinib was 2 mg/kg. Tumors were harvested, sectioned and immunohistochemically stained, and the tumor growth rates and survival times in each group were measured. Blood samples and liver tissues were collected for pharmacokinetic analysis.

Results

The tumor growth rate in Group PA was considerably lower than the other four groups (P=0.000<0.01), and the survival time was significantly prolonged (P=0.000<0.01). The immunohistochemistry results showed that CD31 expression was significantly lower in Group PA than that of the other four groups (P=0.000<0.01). The apatinib concentration in the blood fell below 10 ng/mL within 10 min after TAE and dropped below 1 ng/mL after 8 h. The drug was released continuously in the liver for 36 days, with the highest concentration at the tumor junction (P=0.045<0.05).

Conclusion

PIB effectively targeted apatinib to HCC tissues, achieved a slow and sustained release of the drug in the tumor and considerably reduced the systemic drug concentration. Further experiments showed significantly prolonged survival times and an inhibitory effect on tumor growth.

Treatment Options for Early-Stage Hepatocellular Carcinoma

Patients with early stage hepatocellular carcinoma have good prognosis and are treated with curative intent. Although this cohort of patients is generally defined by limited tumor burden, good liver function, and preserved functional status, there remains utility in further stratification to optimize overall survival and limit post-operative morbidity and mortality. Transplant, resection, ablation, transarterial radioembolization, and transarterial chemoembolization, either as monotherapy or in combination, may play a crucial role in treating this cohort of patients depending on a multitude of factors. In this section, we review each treatment modality and provide general guidelines for patient selection.

Therapy of Intermediate-Stage Hepatocellular Carcinoma: Current Evidence and Clinical Practice

Intermediate-stage Hepatocellular Carcinoma (HCC) represents a wide range of disease burden. Patients with different levels of liver function, tumor size, and number of lesions may all have intermediate-stage disease according to the Barcelona Clinic Liver Cancer (BCLC) staging system. Several minimally invasive image-guided locoregional therapies are available for the treatment of intermediate-stage HCC, including conventional transarterial chemoembolization (cTACE), drug-eluting bead TACE (DEB-TACE), yttrium-90 radioembolization (Y-90 RE), thermal ablation, bland embolization, and combination therapy. Available clinical evidence points to cTACE as the current gold standard for the locoregional treatment of intermediate-stage HCC. DEB-TACE is at best non-inferior to cTACE in terms of survival benefit. Y-90 RE is a maturing therapy, and some institutions have adopted it as first-line therapy for intermediate-stage HCC. Thermal ablation combined with TACE may be used in select patients, while bland embolization has only limited evidence for its use. The combination of locoregional therapy with VEGF inhibitors or immune checkpoint inhibitors has also been explored. This article will examine in detail the clinical evidence supporting available locoregional treatment options for intermediate-stage HCC.

Locoregional Therapies for Hepatocellular Carcinoma: What Has Changed in the Past Ten Years?

The evolution of locoregional therapies in the last decade has been refined with improved patient selection and a development of a more personalized approach. In doing so, there has been associated improved outcomes and less toxicity. With the rapidly changing landscape of systemic therapy, the role of locoregional therapies alone or in combination for downstaging and curative intent will continue to evolve.

Comparison of embolic effect between water-in-oil emulsion and microspheres in transarterial embolization for rat hepatocellular carcinoma model

AIM

To compare two different embolic materials, water-in-oil (W/O) emulsion followed by gelatin particles and microspheres in transarterial embolization (TAE), using a rat hepatocellular carcinoma model.

METHODS

Twenty rats bearing N1S1 cells were divided into the W/O emulsion group and Microsphere group. Water-in-oil emulsion was created by a glass membrane emulsification device. The tumor vascularity was measured by contrast-enhanced ultrasonography 24 h before and 10 min and 48 h after TAE. Tumor necrosis, hepatic infarction ratio surrounding the tumor, and locations of the embolic materials 48 h after TAE were assessed. The changes of serum liver enzymes were also evaluated. Statistical significance was determined by using either the Mann-Whitney U-test or Fisher's exact test.

RESULTS

The tumor vascularity 48 h after TAE was significantly higher in the Microsphere group (20.1 vs. 3.76%, P = 0.016). The overflow of Lipiodol into the portal veins surrounding the tumor was seen, whereas microspheres were seen only in the artery. The percentage of necrotic area and complete response ratio in the W/O emulsion group was significantly higher (99.9 vs. 87.6%, P = 0.029 and 87.5 vs. 28.6%, P = 0.041, respectively). Serum aspartate aminotransferase and serum alanine aminotransferase levels 48 h after TAE were significantly higher in the W/O emulsion group (P < 0.01).

CONCLUSIONS

The embolization using W/O emulsion followed by gelatin particles showed stronger antitumor effects with the occlusion of both the tumor feeding artery and the portal vein compared with microspheres, which occluded only the arteries.

Chemoembolization of liver cancer with doxorubicin-loaded CalliSpheres microspheres: plasma pharmacokinetics, intratumoral drug concentration, and tumor necrosis in a rabbit model

The purpose of this work was to investigate the plasma pharmacokinetics, intratumoral drug concentration, and tumor necrosis after transarterial chemoembolization (TACE) with doxorubicin-loaded CalliSpheres microspheres (CSMs). Sixty rabbits with liver VX2 tumors were assigned into five groups of 12 rabbits each, which received 4 mg of doxorubicin via intravenous injection (IV group), hepatic arterial infusion (IA group), conventional TACE (cTACE group), CSM-TACE (CSM low-dose group), and 8 mg of doxorubicin via CSM-TACE (CSM high-dose group), respectively. Doxorubicin concentrations in plasma, tumor, and adjacent hepatic parenchyma were measured at various timepoints after treatment, and tumor necrosis percentage and liver enzymes were also assessed. The peak plasma concentration of doxorubicin was significantly lower in the three TACE groups compared to IV and IA group (P < 0.05), while doxorubicin concentrations in tumor and adjacent hepatic parenchyma were higher in the two CSM groups compared with IV, IA, and cTACE groups at 3 days and 7 days after treatment (P < 0.05). The percentages of tumor necrosis at 3 and 7 days after treatment were significantly higher in three TACE groups (all higher than 50%) compared with IV group and IA group (both lower than 25%) (P < 0.05), and the highest tumor necrosis percentage was achieved in CSM high-dose group. The three TACE groups showed transient increases in transaminases levels after treatment, in which the peak transaminases levels were significantly lower in the two CSM groups than those in cTACE group (P < 0.05). CSM achieves an effective delivery of doxorubicin into liver cancer. High-dose doxorubicin improves tumoricidal capacity while not impairing the safety of the doxorubicin-loaded CSM.

Quantification of Functional MR Predicts Early Response in Post-doxorubicin Drug-Eluting Beads Chemoembolization for Hepatocellular Carcinoma

BACKGROUND

The purpose of this study was to assess the value of functional MRI (fMRI) of post-doxorubicin drug-eluting beads transcatheter arterial chemoembolization (DEB-TACE) for hepatocellular carcinoma (HCC) as an early imaging biomarker of response to therapy.

METHODS

This prospective analysis included 21 consecutive patients undergoing fMRI before and after DEB-TACE at a single medical center from January 2013 to December 2014. Functional MRI, including relative changes in apparent diffusion coefficient (ADC) and choline levels measured at hydrogen-1 magnetic resonance spectroscopy (MRS) of treated lesions, was recorded at baseline before DEB-TACE, and at 1, 2, and 4 weeks after DEB-TACE therapy. Assessment of tumor response was based on dynamic contrast-enhanced computer tomography imaging response according to modified response evaluation criteria in solid tumors.

RESULTS

At post-therapy, 76% (n = 16) of patients demonstrated objective tumor response, 10% (n = 2) had stable disease, and 3 (14%) had progressive disease. Stable disease and progressive disease were designated as non-response. At week 2, the mean change in ADC value of responsive tumors was 0.35 ± 0.24 mm²/s, which was greater than that of non-response tumors (mean 0.01 ± 0.13 × 10^-3 mm²/s) (P = 0.006). Significant differences were found in mean choline/water ratio between responsive (7.8 ± 4.9 × 10^-3) and non-responsive (17.2 ± 4.9 × 10^-3) tumors (P = 0.005). Composite scores of choline/water ratio and relative change of ADC showed significantly better diagnostic accuracy in non-responsive tumors than responsive tumors (area under the curve = 1.0; P < 0.001).

CONCLUSIONS

Combined DWI and MRS may be used as an early imaging biomarker of therapy response in HCC patients after chemoembolization therapy.

Idarubicin-Loaded ONCOZENE Drug-Eluting Bead Chemoembolization in a Rabbit Liver Tumor Model: Investigating Safety, Therapeutic Efficacy, and Effects on Tumor Microenvironment

PURPOSE

To investigate toxicity, efficacy, and microenvironmental effects of idarubicin-loaded 40-μm and 100-μm drug-eluting embolic (DEE) transarterial chemoembolization in a rabbit liver tumor model.

MATERIALS AND METHODS

Twelve male New Zealand White rabbits with orthotopically implanted VX2 liver tumors were assigned to DEE chemoembolization with 40-μm (n = 5) or 100-μm (n = 4) ONCOZENE microspheres or no treatment (control; n = 3). At 24-72 hours postprocedurally, multiparametric magnetic resonance (MR) imaging including dynamic contrast-enhanced (DCE), diffusion-weighted imaging (DWI), and biosensor imaging of redundant deviation in shifts (BIRDS) was performed to assess extracellular pH (pHe), followed by immediate euthanasia. Laboratory parameters and histopathologic ex vivo analysis included fluorescence confocal microscopy and immunohistochemistry.

RESULTS

DCE MR imaging demonstrated a similar degree of devascularization of embolized tumors for both microsphere sizes (mean arterial enhancement, 8% ± 12 vs 36% ± 51 in controls; P = .07). Similarly, DWI showed postprocedural increases in diffusion across the entire lesion (apparent diffusion coefficient, 1.89 × 10^-3 mm²/s ± 0.18 vs 2.34 × 10^-3 mm²/s ± 0.18 in liver; P = .002). BIRDS demonstrated profound tumor acidosis at baseline (mean pHe, 6.79 ± 0.08 in tumor vs 7.13 ± 0.08 in liver; P = .02) and after chemoembolization (6.8 ± 0.06 in tumor vs 7.1 ± 0.04 in liver; P = .007). Laboratory and ex vivo analyses showed central tumor core penetration and greater increase in liver enzymes for 40-μm vs 100-μm microspheres. Inhibition of cell proliferation, intratumoral hypoxia, and limited idarubicin elution were equally observed with both sphere sizes.

CONCLUSIONS

Noninvasive multiparametric MR imaging visualized chemoembolic effects in tumor and tumor microenvironment following DEE chemoembolization. Devascularization, increased hypoxia, coagulative necrosis, tumor acidosis, and limited idarubicin elution suggest ischemia as the predominant therapeutic mechanism. Substantial size-dependent differences indicate greater toxicity with the smaller microsphere diameter.

Advances in the treatment of hepatocellular carcinoma using drug-eluting beads

Hepatocellular carcinoma (HCC) is one of the most common types of malignant tumor. Although radical surgery and liver transplantation are possible cures for the disease, most patients are beyond the optimum stage for radical treatment at the time of diagnosis. Transarterial chemoembolization (TACE) is the first choice of treatment for advanced HCC. Owing to the widespread use of conventional TACE (cTACE), the problems with this treatment cannot be ignored. Drug-eluting beads (DEBs), a new type of embolization material, appear to overcome the problems of cTACE, and they have other advantages such as synchronous controlled continuous drug release after chemotherapy and embolization and low blood concentrations after treatment. This review summarizes the recent advances in the use of DEB-TACE to treat HCC.

Handling and performance characteristics of a new small caliber radiopaque embolic microsphere

The in vitro and in vivo handling and performance characteristics of a small caliber radiopaque embolic microsphere, 40–90 μm DC Bead LUMI™ (LUMI40‐90), were studied. Microsphere drug loading and elution and effects on size, suspension, and microcatheter delivery were evaluated using established in vitro methodologies. In vivo evaluations of vascular penetration (rabbit renal artery embolization), long‐term biocompatibility and X‐ray imaging properties, pharmacokinetics and local tissue effects of both doxorubicin (Dox) and irinotecan (Iri) loaded microspheres (swine hepatic artery embolization) were conducted. Compared to 70–150 μm DC Bead LUMI (LUMI70‐150), LUMI40‐90 averaged 70 μm versus 100 μm, which was unchanged upon drug loading. Handling, suspension, and microsphere delivery studies were successfully performed. Dox loading was faster (20 min) and Iri equivalent (<10 min) while drug elution rates were similar. Contrast suspension times were longer with no delivery complications. Vascular penetration was statistically greater (rabbit) with no unexpected adverse safety findings (swine). Microspheres ± drug were visible under X‐ray imaging (CT) at 90 days. Peak plasma drug levels and area under the curve were greater for LUMI40‐90 compared to LUMI70‐150 but comparable to 70–150 μm DC BeadM1™ (DC70‐150). Local tissue effects showed extensive hepatic necrosis for Dox, whereas Iri displayed lower toxicity with more pronounced lobar fibrosis. LUMI40‐90 remains suspended for longer and have greater vessel penetration compared to the other DC Bead LUMI sizes and are similarly highly biocompatible with long‐term visibility under X‐ray imaging. Drug loading is equivalent or faster with pharmacokinetics similar to DC70‐150 for both Dox and Iri.

The Dual Role of the Liver in Nanomedicine as an Actor in the Elimination of Nanostructures or a Therapeutic Target

The development of nanostructures for therapeutic purpose is rapidly growing, following the results obtained in vivo in animal models and in the clinical trials. Unfortunately, the potential therapeutic efficacy is not completely exploited, yet. This is mainly due to the fast clearance of the nanostructures in the body. Nanoparticles and the liver have a unique interaction because the liver represents one of the major barriers for drug delivery. This interaction becomes even more relevant and complex when the drug delivery strategies employing nanostructures are proposed for the therapy of liver diseases, such as hepatocellular carcinoma (HCC). In this case, the selective delivery of therapeutic nanoparticles to the tumor microenvironment collides with the tendency of nanostructures to be quickly eliminated by the organ. The design of a new therapeutic approach based on nanoparticles to treat HCC has to particularly take into consideration passive and active mechanisms to avoid or delay liver elimination and to specifically address cancer cells or the cancer microenvironment. This review will analyze the different aspects concerning the dual role of the liver, both as an organ carrying out a clearance activity for the nanostructures and as target for therapeutic strategies for HCC treatment.