Transarterial chemoembolization alone and in combination with other therapies: a comparative study in an animal HCC model

Evaluation of two different transarterial chemoembolization protocols using Lipiodol and degradable starch microspheres in therapy of hepatocellular carcinoma: a prospective trial

BACKGROUND

This prospective randomized trial is designed to compare the performance of conventional transarterial chemoembolization (cTACE) using Lipiodol-only with additional use of degradable starch microspheres (DSM) for hepatocellular carcinoma (HCC) in BCLC-stage-B based on metric tumor response.

METHODS

Sixty-one patients (44 men; 17 women; range 44-85) with HCC were evaluated in this IRB-approved HIPPA compliant study. The treatment protocol included three TACE-sessions in 4-week intervals, in all cases with Mitomycin C as a chemotherapeutic agent. Multiparametric magnetic resonance imaging (MRI) was performed prior to the first and 4 weeks after the last TACE. Two treatment groups were determined using a randomization sheet: In 30 patients, TACE was performed using Lipiodol only (group 1). In 31 cases Lipiodol was combined with DSMs (group 2). Response according to tumor volume, diameter, mRECIST criteria, and the development of necrotic areas were analyzed and compared using the Mann-Whitney-U, Kruskal-Wallis-H-test, and Spearman-Rho. Survival data were analyzed using the Kaplan-Meier estimator.

RESULTS

A mean overall tumor volume reduction of 21.45% (± 62.34%) was observed with an average tumor volume reduction of 19.95% in group 1 vs. 22.95% in group 2 (p = 0.653). Mean diameter reduction was measured with 6.26% (± 34.75%), for group 1 with 11.86% vs. 4.06% in group 2 (p = 0.678). Regarding mRECIST criteria, group 1 versus group 2 showed complete response in 0 versus 3 cases, partial response in 2 versus 7 cases, stable disease in 21 versus 17 cases, and progressive disease in 3 versus 1 cases (p = 0.010). Estimated overall survival was in mean 33.4 months (95% CI 25.5-41.4) for cTACE with Lipiosol plus DSM, and 32.5 months (95% CI 26.6-38.4), for cTACE with Lipiodol-only (p = 0.844), respectively.

CONCLUSIONS

The additional application of DSM during cTACE showed a significant benefit in tumor response according to mRECIST compared to cTACE with Lipiodol-only. No benefit in survival time was observed.

Transcriptional analysis and differentially expressed gene screening of spontaneous liver tumors in CBA/CaJ mice

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths worldwide due to its frequent metastasis, tumor recurrence, and lack of curative treatment. However, the underlying molecular mechanisms involved in HCC progression remain unclear. Here, we analyzed the global gene expression of spontaneous liver tumor tissue from CBA/CaJ mice by RNA-Seq and identified 10,706 and 10,374 genes in the normal and liver tumor groups, respectively. Only 9793 genes were expressed in both, 913 genes were identified in only the liver tumor group, and 581 genes were found in normal liver tissues. There were 2054 differentially expressed genes (DEGs), with 975 down-regulated genes and 1079 up-regulated genes. Gene ontology (GO) term enrichment analysis showed that 43 up-regulated genes were significantly associated with cell cycle regulation and hundreds of up-regulated genes were related to cell migration, adhesion, or metabolic processes. KEGG pathway enrichment also demonstrated that some DEGs were tightly associated with the cell cycle, extracellular matrix (ECM)-receptor interactions, as well as protein digestion and absorption pathways, indicating that the activation of these oncogenic cascades was closely related to tumor liver progression in CBA/CaJ mice. Ninety-three genes with elevated expression levels preferentially localized in microtubules, kinetochores, and spindles play an important role during mitosis and meiosis and are associated with the reorganization of the cytoskeleton in cancer cells during migration and invasion. Some ECM-related genes were significantly different in the tumor group, including collagen types I, III, IV, V, and VI, non-collagenous glycoproteins, laminin, and fibronectin. We further validated the functions of upregulated genes, such as cyclin-dependent kinase 1 (CDK1) and polo-like kinase 1 (PLK1), with regards to cell cycle regulation, apoptosis, and proliferation in normal human liver or liver tumor-derived cell lines. Our results indicated that the cell cycle dysregulation, ECM-receptor interaction, and cytoskeleton-associated genes in mouse livers may promote HCC progression and deciphering the function of the genes will help investigators understand the underlying molecular mechanism of HCC.

The Use of the Woodchuck as an Animal Model for Evaluation of Transarterial Embolization

There are many shortcomings of current animal models as surrogates of hepatocellular carcinoma that handicap preclinical testing of embolization agents. The present study explores the feasibility of using the woodchuck (Marmota monax) as an animal model for the testing of novel embolization agents. Four woodchucks underwent magnetic resonance imaging, angiography, and left lobar hepatic artery particle embolization. Percutaneous access, arteriography, and lobar embolization were successful in all animals, with angiographic stasis obtained in the target vessel with minimal reflux of embolic material. These results support the feasibility of the woodchuck as an animal model for preclinical testing of embolization agents.

The effect of JAK2 knockout on inhibition of liver tumor growth by inducing apoptosis, autophagy and anti-proliferation via STATs and PI3K/AKT signaling pathways

Liver cancer is a leading cause of cancer death, making it as the second most common cause for death from cancer globally. Though many studies before have explored a lot for liver cancer prevention and treatment, there are still a lot far from to know based on the molecular mechanisms. Janus kinase 2 (JAK2) has been reported to play an essential role in the progression of apoptosis, autophagy and proliferation for cells. Therefore, we were aimed to investigate the underlying mechanisms by which JAK2 performed its role in ameliorating liver cancer. JAK2 knockout liver cancer cell lines were involved for our experiments in vitro and in vivo. Western blotting, quantitative RT-PCR (qRT-PCR), ELISA, Immunohistochemistry, and flow-cytometric analysis were used to determine the key signaling pathway regulated by JAK2 for liver cancer progression. Data here indicated that JAK2, indeed, expressed highly in cancer cell lines compared to the normal liver cells. And apoptosis and autophagy were found in JAK2 knockout liver cancer cells through activating Caspase-3, Cyclin-D1 and mTOR regulated by STAT3/5 and PI3K/AKT signaling pathway. And also, the liver cancer cells proliferation was inhibited. In addition, tumor size and weight were reduced by knockout of JAK2 in vivo experiments. These findings demonstrated that JAK2 and its down-streaming signaling pathways play a direct role in the progression of liver cancer possibly. To our knowledge, it was the first time to evaluate the role of JAK2 knockout in improving liver cancer from apoptosis, autophagy and proliferation, which could be a potential target for future therapeutic approach clinically.

Positive feedback loop between cancer stem cells and angiogenesis in hepatocellular carcinoma

Anti-angiogenesis-related therapies have become the standard care for patients with advanced hepatocellular carcinoma (HCC), as HCC is a highly vascularized solid tumor. Unfortunately, only modest and limited efficacies are observed. Emerging evidence have attributed to the limited efficacy to the presence of cancer stem cells (CSCs) in the tumor. CSCs predominantly drives angiogenesis via releasing proangiogenic factors and exosomes. They have the ability to resistant intratumoral hypoxia via autophagy or by directly forming the tubular structure to obtain blood. On the other hand, the vascular niche in tumor microenvironment also releases growth factors via juxtacrine and paracrine mechanisms to support the growth of CSCs and maintain its stemness features. This positive feedback loop between angiogenesis and CSCs exists in liver tumor microenvironment that is responsible for the development and poor prognosis of HCC. In this review, we summarize recent advances in our understanding of the crosstalks between angiogenesis and CSCs, and their interactions in liver tumor microenvironment and their purpose that an effective anti-angiogenic therapy should also target CSCs for HCC treatment.

Development of a High-Throughput Molecular Imaging-Based Orthotopic Hepatocellular Carcinoma Model

We have developed a novel orthotopic rat hepatocellular (HCC) model and have assessed the ability to use bioluminescence imaging (BLI), positron emission tomography (PET), and ultrasound for early tumor detection and monitoring of disease progression.  Briefly, rat HCC cells were stably transfected with click beetle red as a reporter gene for BLI. Tumor cells were injected under direct visualization into the left or middle lobe of the liver in 37 rats. In six animals, serial PET, BLI, and ultrasound imaging were performed at 10-time points in 28 days. The remainder of the animals underwent PET imaging at 14 days. Tumor implantation was successful in 34 of 37 animals (91.9%). In the six animals that underwent serial imaging, tumor formation was first detected with BLI on Day 4 with continued increase through Day 21, and hypermetabolic activity on PET was first noted on Days 14-15 with continued increase through Day 28. PET activity was seen on Day 14 in the 28 other animals that demonstrated tumor development. Anatomic tumor formation was detected with ultrasound at Days 10-12 with continued growth through Day 28. The first metastases were detected by PET after Day 24.        We have successfully developed and validated a novel orthotopic HCC small animal model that permits longitudinal assessment of change in tumor size using molecular imaging techniques. BLI is the most sensitive imaging method for detection of early tumor formation and growth. This model permits high-throughput in vivo evaluation of image-guided therapies.

Synthesis and application of strawberry-like Fe3O4-Au nanoparticles as CT-MR dual-modality contrast agents in accurate detection of the progressive liver disease

Development of non-invasive assay for the accurate diagnosis of progressive liver diseases (e.g., fatty liver and hepatocellular carcinoma (HCC)) is of great clinical significance and remains to be a big challenge. Herein, we reported the synthesis of strawberry-like Fe3O4-Au hybrid nanoparticles at room temperature that simultaneously exhibited fluorescence, enhanced X-ray attenuation, and magnetic properties. The results of in vitro fluorescence assay showed that the nanoparticles had significant photo-stability and could avoid the endosome degradation in cells. The in vivo imaging of normal mice demonstrated that the Fe3O4-Au nanoparticles provided 34.61-fold contrast enhancement under magnetic resonance (MR) guidance 15 min post the administration. Computed tomography (CT) measurements showed that the highest Hounsfield Unit (HU) was 174 at 30 min post the injection of Fe3O4-Au nanoparticles. In vivo performance of the Fe3O4-Au nanoparticles was further evaluated in rat models bearing three different liver diseases. For the fatty liver model, nearly homogeneous contrast enhancement was observed under both MR (highest contrast ratio 47.33) and CT (from 19 HU to 72 HU) guidances without the occurrences of focal nodules or dysfunction. For the cirrhotic liver and HCC, pronounced enhancement under MR and CT guidance could be seen in liver parenchyma with highlighted lesions after Fe3O4-Au injection. Furthermore, pathological, hematological and biochemical analysis revealed the absence of acute and chronic toxicity, confirming the biocompatibility of our platform for in vivo applications. Collectively, These Fe3O4-Au nanoparticles showed great promise as a candidate for multi-modality bio-imaging.

Arsenic trioxide: marked suppression of tumor metastasis potential by inhibiting the transcription factor Twist in vivo and in vitro

PURPOSE

Arsenic trioxide (ATO) has been found effective in several types of cancer cells, including acute promyelocytic leukemia, and recently in hepatocellular carcinoma (HCC). In this study, we investigated the role of ATO in regulating the invasive activity of HCC after transarterial embolization (TAE).

METHODS

Cell migration and invasion were observed using Transwell and wound-healing assay. The molecular changes in E-cadherin, N-cadherin, and Vimentin of surviving tumor cells were determined by Western blotting. The effects of ATO on Twist activity of the tumor cells were further analyzed. In animal study, 40 male buffalo rats implanted with McA-RH7777 tumor in the liver were randomly divided into four groups: control, TAE, ATO, and TAE + ATO. TAE procedures were performed on the 14th day after implantation. Lung metastases were observed using fluorescence imaging, and the molecular changes in residual tumor cells were evaluated by Western blotting or immunohistochemistry. Tumor growth and survival analysis were also evaluated.

RESULTS

Arsenic trioxide markedly reduced cell migration and invasiveness, which were enhanced by hypoxia after TAE. Western blot analysis revealed ATO inhibited the expression of epithelial-mesenchymal transition (EMT) markers by suppressing Twist. The marked suppression effect of ATO on invasiveness and metastatic potential related to EMT was also shown in tissue.

CONCLUSION

The results of this study demonstrated that ATO is an effective anticancer agent in combination with TAE in the treatment of HCC, by suppressing tumor progression and metastasis via selectively inducing tumor cell apoptosis and arresting EMT by inhibiting the Twist activation.

Intra-arterial interleukin-12 gene delivery combined with chemoembolization: anti-tumor effect in a rabbit hepatocellular carcinoma (HCC) model

BACKGROUND

Interleukin-12 (IL-12), a cytokine naturally secreted by activated dendritic cells and monocytes/macrophages, is known as a key anti-tumor agent in many tumor models, including hepatocellular carcinoma (HCC) models.

PURPOSE

To evaluate the anti-tumor effect of intra-arterial IL-12 gene delivery alone and in combination with transcatheter arterial chemoembolization (TACE) in rabbit VX2 liver cancer model.

MATERIAL AND METHODS

Rabbits with VX2 liver tumors were randomized into four groups, eight in each group. After laparotomy and insertion of a 30-gauge needle into the proper hepatic artery, the following interventional procedure protocols were applied: 0.9% saline solution (group A, control), TACE (group B, TACE alone, lipiodol + mitomycin), intra-arterial interleukin-12 gene infusion (group C, IL-12 alone), and intra-arterial interleukin-12 gene infusion in combination with TACE (group D, IL-12 plus TACE). Growth ratio was estimated by computed tomography. To analyze apoptotic index, tumor tissues were explanted for terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) staining, 14 days after therapy.

RESULTS

Significant differences of the relative tumor growth ratio were observed in TACE alone group and IL-12 plus TACE group in comparison with control (P < 0.05, ANOVA, Tukey's HSD correction) but not between IL-12 alone and control, or IL-12 plus TACE group and TACE alone group (P > 0.05). Significant changes of the apoptotic index were observed in group D in comparison with remaining three groups (P < 0.05). The difference between group C and group A was not significant statistically (P > 0.05).

CONCLUSION

Intra-arterial interleukin-12 gene therapy combined with TACE has a potent anti-tumor effect in rabbit VX2 liver cancer in comparison with TACE alone.

Transarterial chemoembolization with drug-eluting beads in hepatocellular carcinoma: usefulness of contrast saturation features on cone-beam computed tomography imaging for predicting short-term tumor response

PURPOSE

To evaluate the predictability of the short-term tumor response and the clinical usefulness of cone-beam computed tomography (CT) performed immediately after drug-eluting bead (DEB) transarterial chemoembolization in patients with unresectable hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

This retrospective study comprised 90 patients (male-to-female ratio = 66:24; mean age, 60.4 y) with 119 tumors (mean size, 3.2 cm). All patients underwent DEB transarterial chemoembolization and received cone-beam CT after embolization. The marginal contrast saturation was defined as a contrast stasis that was observed along the margin of the tumor on the cone-beam CT images. The degree of marginal contrast saturation was calculated as a percentage and was classified into five grades in 25% increments. The degree of marginal contrast saturation and the tumor response were correlated based on follow-up imaging.

RESULTS

There was a complete response in 63.8% (n = 76) of all tumors. Partial response, stable disease, and progressive disease were identified in 21.8% (n = 26), 13.4% (n = 16), and 0.8% (n = 1) of tumors. Marginal contrast saturation by cone-beam CT was 86%± 16.3, 73.2%± 28.8, 16.9%± 27.2, and 0% for complete response, partial response, stable disease, and progressive disease, which indicated a significant correlation of a higher contrast saturation with a better response (P<.001) by follow-up imaging criteria. The positive predictive value of the G5 group showing a complete response was 98.1%.

CONCLUSIONS

Marginal contrast saturation showed a high positive predictive value for short-term tumor response. This technique may improve the success rates of DEB transarterial chemoembolization procedures and may reduce technical difficulties and shorten procedural time.

A comparative study on the hepatoprotective action of bear bile and Coptidis Rhizoma aqueous extract on experimental liver fibrosis in rats

AIM OF THE STUDY

Bear bile and Coptidis Rhizoma have been used in Chinese medicine with a long tradition in treating heat-diseases. Both bear bile and Coptidis Rhizoma are used to treat liver diseases in clinical practice of Chinese Medicine. Since bears are currently endangered, it raises the question whether the use of bear bile is ethical. To look for substitute for bear bile, the aim of this study is to compare the anti-fibrotic effects of Coptidis Rhizoma and its major component berberine with the actions of bear bile and its major compound tauroursodeoxycholic acid on experimental liver fibrosis in rats.

METHOD

Quality assessment was conducted with high performance liquid chromatography. The experimental liver fibrosis in rats was induced by carbon tetrachloride, alcohol, and bile duct ligation respectively. The biochemical criteria in the blood and tissue samples were measured to evaluate the anti-fibrotic properties and underlying mechanisms of the drugs.

RESULTS

Coptidis Rhizoma Aqueous Extract (CRAE), berberine, and bear bile exerted anti-fibrotic properties on various liver fibrosis models in rats. CRAE and berberine significantly reduced the peroxidative stress in liver through increasing the superoxide dismutase enzyme activity. CRAE and berberine were able to excrete bilirubin products from the liver and protect hepatocytes from cholestatic damage. The effect of CRAE and berberine are comparable to that of bear bile.

CONCLUSION

Instead of using bear bile, CRAE and berberine can be potential substitutes in treating liver fibrosis.

Disposition of ultrasound sensitive polymeric drug carrier in a rat hepatocellular carcinoma model

RATIONALE AND OBJECTIVES

A doxorubicin-loaded microbubble has been developed that can be destroyed with focused ultrasound resulting in fragments, or "nanoshards" capable of escaping through the leaky tumor vasculature, promoting accumulation within the interstitium. This study uses a rat liver cancer model to examine the biodistribution and tumoral delivery of this microbubble platform compared with de novo drug-loaded polymer nanoparticles and free doxorubicin.

MATERIALS AND METHODS

Microbubbles (1.8 μm) and 217-nm nanoparticles were prepared containing 14-C labeled doxorubicin. Microbubbles, nanoparticles, a combination of the two, or free doxorubicin were administered intravenously in rats bearing hepatomas, concomitant with tumor insonation. Doxorubicin levels in plasma, organs, and tumors were quantified after 4 hours and 7 and 14 days. Tumors were measured on sacrifice and evaluated with autoradiography and histology.

RESULTS

Animals treated with microbubbles had significantly lower plasma doxorubicin concentrations (0.466 ± 0.068%/mL) compared with free doxorubicin (3.033 ± 0.612%/mL, P = .0019). Drug levels in the myocardium were significantly lower in animals treated with microbubbles compared to free doxorubicin (0.168%/g tissue vs. 0.320%/g, P = .0088). Tumors treated with microbubbles showed significantly higher drug levels than tumors treated with free doxorubicin (2.491 ± 0.501 %/g vs. 0.373 ± 0.087 %/g, P = .0472). These tumors showed significantly less growth than tumors treated with free doxorubicin (P = .0390).

CONCLUSIONS

Doxorubicin loaded microbubbles triggered with ultrasound provided enhanced, sustained drug delivery to tumors, reduced plasma and myocardium doxorubicin levels, and arresting tumor growth. The results suggest that in situ generation of nano particles provides a superior treatment over injection of free drug and also de novo synthesized nanoparticles.

Hepatocellular carcinoma: insight from animal models

Hepatocellular carcinoma (HCC) ranks as the third most common cause of death from cancer worldwide. Although major risk factors for the development of HCC have been defined, many aspects of the evolution of hepatocellular carcinogenesis and metastasis are still unknown. Suitable animal models are, therefore, essential to promote our understanding of the molecular, cellular and pathophysiological mechanisms of HCC and for the development of new therapeutic strategies. This Review provides an overview of animal models that are relevant to HCC development, metastasis and treatment. For HCC development, this Review focuses on transgenic mouse models of HBV and HCV infection, which provide experimental evidence that viral genes could initiate or promote liver carcinogenesis. Animal models of HCC metastasis provide platforms to elucidate the mechanisms of HCC metastasis, to study the interaction between the microenvironment and HCC invasion and to conduct intervention studies. In addition, animal models have been developed to investigate the effects of new treatment modalities. The criteria for establishing ideal HCC animal models are also discussed.

Combination therapy of transcatheter arterial chemoembolization and arterial administration of antiangiogenesis on VX2 liver tumor

PURPOSE

This study was designed to evaluate the antitumorigenic efficiency of Endostar (an antiangiogenic agent) arterially administrated combined with transcatheter arterial chemoembolization (TACE) on liver tumor, and validation of perfusion CT for quantitative measurements of the results.

EXPERIMENTAL DESIGN

Thirty rabbits bearing VX2 liver tumors were randomly and equally distributed into three groups. One of the following treatment protocols was performed in each group: 1) group 1 was treated with TACE and simultaneously arterially administrated Endostar; 2) group 2 with TACE alone, and 3) a control group that had saline injected through hepatic artery. Routine CT scan was performed before treatment, and perfusion CT imaging was performed 2 weeks after treatment. Immunohistochemical biomarkers of microvascular density (MVD) and the expression of vascular endothelial growth factor (VEGF) were measured for assessments of angiogenesis.

RESULTS

We observed a statistically significant reduction from the control in the volume, growth rate, and size of the tumor 2 weeks after treatment with both TACE plus Endostar and with TACE alone (P < 0.01). Although there was no statistically significant difference in tumor size between the group with TACE plus Endostar and the group with TACE alone (P > 0.05), MVD and VEGF were significantly less expressed in the TACE plus Endostar group than both groups with TACE alone and the control group (P < 0.01). Blood flow (BF), blood volume (BV), and permeability-surface area products (PS) in the group with TACE plus Endostar on perfusion CT were significantly higher than other two groups (P < 0.05), which were positively correlated with the MVD and VEGF values (P < 0.05).

CONCLUSIONS

TACE with arterial administration of Endostar simultaneously significantly inhibited the angiogenesis biomarkers associated with TACE in a rabbit model bearing VX2 liver tumor, which indicates that the combined treatment protocol may have potential synergistic effects on liver cancer. It also is suggested that perfusion CT may be useful for monitoring antiangiogenic/antivascular treatment in the liver tumors.

Experimental evaluation of inhibitory effect of 10-hydroxycamptothecin on hypoxia-inducible factor-1α expression and angiogenesis in liver tumors after transcatheter arterial embolization

PURPOSE

To evaluate the effect of transcatheter administration of 10-hydroxycamptothecin (HCPT), a hypoxia-inducible factor-1α (HIF-1α) inhibitor, on HIF-1α expression and angiogenesis in liver tumors after transcatheter arterial embolization in an animal model.

MATERIALS AND METHODS

VX2 tumors were implanted in the livers of 30 rabbits. The animals were divided randomly into three groups of 10 animals each. Group 1 animals received hepatic intraarterial infusion of distilled water. Group 2 animals received iodized oil infusion followed by embolization with 150-250 μm of polyvinyl alcohol particles. Group 3 animals received infusion of a mixture of HCPT (1 mg/kg body weight) with iodized oil followed by the particle embolization. Six hours or 3 days after transcatheter treatment, the animals were sacrificed, and the tumor samples were harvested. Immunohistochemical staining was performed to evaluate the levels of HIF-1α and vascular endothelial growth factor (VEGF) protein as well as microvessel density.

RESULTS

The levels of HIF-1α and VEGF and microvessel density in tumors of group 2 were significantly higher than those of group 1 or 3 (P < .05). However, no significant differences were noted in tumors between group 1 and 3 (P > .05). HIF-1α levels were significantly correlated with VEGF levels (r = .587, P = .001) and microvessel density (r = .527, P = .003).

CONCLUSIONS

Transcatheter infusion of HCPT has an inhibitory effect on HIF-1α expression and angiogenesis in liver tumors after transcatheter arterial embolization.

Abdominal magnetic resonance imaging in small rodents using a clinical 1.5 T MR scanner

Because of superior soft-tissue contrast compared to other imaging techniques, non-invasive abdominal magnetic resonance imaging (MRI) is ideal for monitoring organ regeneration, tissue repair, cancer stage, and treatment effects in a wide variety of experimental animal models. Currently, sophisticated MR protocols, including technically demanding procedures for motion artefact compensation, achieve an MRI resolution limit of < 100 microm under ideal conditions. However, such a high spatial resolution is not required for most experimental rodent studies. This article describes both a detailed imaging protocol for MR data acquisition in a ubiquitously and commercially available 1.5 T MR unit and 3-dimensional volumetry of organs, tissue components, or tumors. Future developments in MR technology will allow in vivo investigation of physiological and pathological processes at the cellular and even the molecular levels. Experimental MRI is crucial for non-invasive monitoring of a broad range of biological processes and will further our general understanding of physiology and disease.

Strategies for the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) generally develops as a consequence of underlying liver disease, most commonly viral hepatitis. The development of HCC follows an orderly progression from cirrhosis to dysplastic nodules to early cancer development, which can be reliably cured if discovered before the development of vascular invasion (typically occurring at a tumor diameter of approximately 2 cm). The identifiable population at risk makes screening a realistic possibility, and liver imaging is recommended every 6 months for patients with cirrhosis. For patients with preserved liver function and no portal hypertension who develop HCC that is confined to one region of the liver, resection is the preferred treatment. If resection is not possible because of poor liver function, and the HCC is within the Milan criteria (1 nodule > or =5 cm, 2-3 nodules > or =3 cm), liver transplantation is the treatment of choice. To prevent tumor progression while waiting, nonsurgical treatments including percutaneous ethanol injection, radiofrequency ablation, and transarterial chemoembolization are employed, but drop-out from the waiting list remains a problem. Living donor transplantation is an alternative that can eliminate drop-out and enable liver transplantation for patients with HCC whose disease does not fall within the Milan criteria. There is a need for more effective adjuvant therapies after resection and liver transplantation; newer antiangiogenic agents offer hope for improved outcomes in the future.

Radiofrequency ablation after transarterial embolization as therapy for patients with unresectable hepatocellular carcinoma

PURPOSE

To evaluate the usefulness of transcatheter arterial embolization (TAE) followed by radiofrequency ablation (RFA) as combined treatment for unresectable hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

Thirty-six consecutive patients (cirrhosis, Child-Pugh class A or B) with solitary or oligonodular HCC were treated (41 lesions; mean size, 58.9 mm; range, 30-120 mm). RFA was performed after one TAE treatment. Local efficacy was evaluated with multiphasic computed tomography (CT) performed an average of two months after RFA and once during later follow-up.

RESULTS

The mean follow-up period was 16 months (range, 2-45 months). Technical success (namely, complete tumor devascularization during the arterial phase) was achieved for 59% of lesions at the first CT evaluation and for 46% at the second evaluation. Among prognostic factors included in the analysis, only lesion diameter (< 50 mm versus > or = 50 mm) was statistically significant in terms of predicting local success (Fisher's exact test: 85% versus 43% at first CT, p<0.01; 70% versus 36% during follow-up, p=0.05). There were no major periprocedural complications. Kaplan-Meier analysis showed survival rates of 84% at 12 months and 57% at 24 months.

CONCLUSIONS

Combined therapy--TAE then RFA--for unresectable HCC lesions in patients with cirrhosis produces a relatively high complete local response rate compared with TAE or RFA alone. Our results, considered with those from other case series, may help design prospective, randomized clinical trials to test combination therapy versus single-modality therapy in terms of risks and benefits.

Large-sized hepatocellular carcinoma (HCC): a neoadjuvant treatment protocol with repetitive transarterial chemoembolization (TACE) before percutaneous MR-guided laser-induced thermotherapy (LITT)

This study aims to evaluate the efficacy and safety of a neoadjuvant treatment protocol with repeated transarterial chemoembolization (TACE) before MR-guided laser-induced thermotherapy (LITT) for large-sized hepatocellular carcinomas (HCC). Repeated TACE (mean, 3.5 treatments per patient) was performed in 48 patients with neoadjuvant intention (the largest lesion was between 50 and 80 mm in diameter, and there were no more than five lesions). For the TACE treatment, we used 10 mg/m(2) mitomycin, 10 ml/m(2) Lipiodol and microspheres. The tumor volume was measured by MRI. Lipiodol retention of the tumors was evaluated with CT. After the diameter of the tumors had decreased to less than 50 mm, the patients were treated with MR-guided LITT 4 to 6 weeks after embolization. Repeated TACE reduced the tumor size in 32 patients (66.7%), forming the basis for performing MR-guided LITT procedures. These patients received one to four laser treatments (mean, 1.9 per patient) for tumor ablation, resulting in a median survival of 36.0 months after the first treatment. For the remaining patients, no reduction in tumor size was achieved in 12 patients and disease progression in 4 patients. Neoadjuvant TACE appears to be an effective treatment of large-sized HCC, which extends the indication for MR-guided LITT.

Effect of Transcatheter Hepatic Arterial Embolization on Angiogenesis in an Animal Model

OBJECTIVES

Transcatheter arterial embolization (TAE) is used for the treatment of patients with malignant liver tumors. However, the proangiogenesis effect of TAE-associated hypoxia has not been adequately studied. The goal of this study was to determine angiogenic activity in tumors subjected to TAE by evaluating the tumor microvessel density (MVD).

MATERIALS AND METHODS

Mammary cancer 13762 NF tumor cells were inoculated into the livers of male Sprague-Dawley rats. TAE was performed 12-14 days after tumor inoculation. Rats were divided into 4 groups on the basis of treatment type. Control group animals (n = 16) were subjected to sham TAE without polyvinyl alcohol (PVA) particles. Animals in the other 3 groups were subjected to TAE with 1 (n = 11), 2 (n = 8), or 3 (n = 10) mg of PVA particles. Rats were killed 3-6 hours or 2 or 3 days after embolization, and the liver tumor tissues were dissected and frozen in liquid nitrogen. Tumor tissue slides were prepared, stained with CD-31, and evaluated for MVD. Blood samples collected just before sacrificing the animals were used to measure serum vascular endothelial growth factor (VEGF) levels.

RESULTS

Tumors treated with TAE showed varying degrees of central necrosis with residual viable tumor cells in the periphery. Tumor MVD in animals treated with TAE was significantly higher than that in the control group (23.6 versus 17.5; P = 0.001). Although the MVD in animals treated with TAE using 1 mg of PVA was higher than that in the control group, this difference was not statistically significant. TAE using 2 mg of PVA resulted in a significant increase in tumor MVD (25.9 versus 17.5; P = 0.007). Use of 3 mg of PVA did not result in any further increase in MVD. There was a significant increase in tumor MVD in the animals killed 2 or 3 days after TAE compared with the control group (24.5 versus 17.5; P = 0.002). The animals treated with TAE showed a statistically significant increase in VEGF levels compared with the control group.

CONCLUSIONS

TAE of hepatic tumors results in the stimulation of angiogenesis in the residual viable tumor, which could have an adverse effect on the therapeutic efficacy of TAE.

Transcatheter arterial chemoembolization in patients with hepatocellular carcinoma and coexisting hepatic cavernous hemangioma

We investigated the consequence of repeated transcatheter arterial chemoembolization (TACE) for coexisting small hepatic hemangioma in the treatment of patients with hepatocellular carcinomas and describe the imaging features of embolized hemangioma on the follow-up Lipiodol CT and MR. Six of 431 patients with biopsy-confirmed hepatocellular carcinomas, who underwent TACE, also had seven small hepatic cavernous hemangiomas (0.8 approximately 2.3 cm) in the same area of embolization. All six patients underwent repeated TACE All lesions were evaluated with CT and/or MR for the post-treatment follow-up. The outcomes and imaging features of these embolized hemangiomas were reviewed for the change of tumor size, Lipiodol deposition, enhancing pattern as well as embolization complications. Six of the seven hemangiomas did not depict changes in the size or enhancement pattern without being ablated. One hemangioma showed a decrease in size, but still persisted after TACE. All of the hemangiomas showed Lipiodol deposition for 2 approximately 15 months, in which five hemangiomas depicted irregular rim patterns. There is no complication caused by the procedures. The differentiation of small hepatic hemangiomas from viable HCC is important in the post-TACE follow-up to avoid unnecessary repeated embolization.

Radiofrequency thermal ablation (RFA) after transarterial chemoembolization (TACE) as a combined therapy for unresectable non-early hepatocellular carcinoma (HCC)

The treatment of unresectable "non-early" (according to the BCLC classification) hepatocellular carcinoma (HCC) in cirrhotic patients with transcatheter arterial chemoembolization (TACE) followed by radiofrequency ablation (RFA) is retrospectively evaluated and possible prognostic factors of this combined therapy are investigated. Forty-six consecutive cirrhotic patients (Child-Pugh class A or B) with solitary or oligonodular HCC underwent RFA after TACE. The treated lesions were 51 overall (size 30-80 mm, mean 48.9). RFA was performed by a multitined expandable electrodes device after one TACE administration. Local efficacy was evaluated with multiphasic computed tomography (CT) performed an average of 2 months after treatment and then during follow-up. Patient survival rate was also evaluated (follow-up time 1-51 months, mean 15 months). Technical success (defined as complete devascularization during the arterial phase) was achieved in 34/51 lesions (66.7%) at the first CT check and in 29/51 (56.9%) during the succeeding follow-up. Among the considered prognostic factors, only lesion diameter (< or > = 50 mm) was statistically significant in the Fisher's exact test in terms of local control (85.2 vs. 45.8% at first CT, p=.0065; 70.4 vs. 41.7% during follow-up, p=.051). There were two major complications (6.5%): one hepatic failure and one death. A Kaplan-Meier analysis showed survival rates of 89.7% at 12 months and 67.1% at 24 months. Combined therapy for non-early HCC shows a relatively high complete local response (especially in lesions less than 5 cm in diameter) and promising mid-term clinical success. Its overall usefulness has yet to be established by a larger series and risk-benefit analysis.