Simulation model based on non-newtonian fluid mechanics applied to the evaluation of the embolic effect of emulsions of iodized oil and anticancer drug

Lipiodol emulsion as a dual chemoradiation-sensitizer for pancreatic cancer treatment

Pancreatic ductal adenocarcinoma (PDAC) has a low survival rate and limited treatment options. Concurrent chemoradiotherapy is considered beneficial to improve tumor control, but the low drug bioavailability at tumor site and the low radiation tolerance of surrounding healthy organs greatly limits its effectiveness. Lipiodol, a natural drug carrier used in clinical transarterial chemoembolization, has shown potential as a radiosensitizer due to its high Z element iodine composition. Thus, this study aims to repurpose lipiodol as a sensitizer to simultaneously enhance chemo- and radiotherapy for PDAC. To this end, a stable lipiodol emulsion (IOE) loaded with gemcitabine is designed using clinically approved surfactants. At in vivo level, IOE demonstrates better radiotherapeutic effect than existing nanoradiosensitizers and enhanced drug bioavailability over free drug, leading to significant tumor inhibition and improved survival rates under concurrent chemo-radiotherapy. This may due to the sustained drug release, homogenous spatial distribution, and long-term retention ability of IOE in solid PDAC tumor. Furthermore, to better understand the functioning mechanism of drug-loaded IOE, in vitro study is conducted to reveal the ROS- and DNA damage-related therapeutic pathways. Lastly, a comprehensive toxicity assessment also proves the good biocompatibility and safety of as-prepared IOE. This study offers a clinically feasible sensitizer for simultaneous chemoradiotherapy and holds potential for other types of cancer treatment in clinics.

Visualization and Evaluation of Chemoembolization on a 3D Decellularized Organ Scaffold

Transarterial chemoembolization (TACE) has emerged as the mainstay treatment for patients suffering from unresectable intermediate hepatocellular carcinoma and also holds the potential to treat other types of hypervascular cancers such as renal cell carcinoma. However, an in vitro model for evaluating both embolic performance and drug-release kinetics of the TACE embolic agents is still lacking since the current models greatly simplified the in vivo vascular systems as well as the extracellular matrices (ECM) in the organs. Here, we developed a decellularized organ model with preserved ECM and vasculatures as well as a translucent appearance to investigate chemoembolization performances of a clinically widely used embolic agent, i.e., a doxorubicin-loaded ethiodised oil (EO)-based emulsion. We, for the first time, utilized an ex vivo model to evaluate the liquid-based embolic agent in two organs, i.e., liver and kidneys. We found that the EO-based emulsion with enhanced stability by incorporating an emulsifier, i.e., hydrogenated castor oil-40 (HCO), showed an enhanced occlusion level and presented sustained drug release in the ex vivo liver model, suggesting an advantageous therapeutic effect for TACE treatment of hepatocellular carcinoma. In contrast, we observed that drug-release burst happened when applying the same therapy in the kidney model even with the HCO emulsifier, which may be explained by the presence of the specific renal vasculature and calyceal systems, indicating an unfavorable effect in the renal tumor treatment. Such an ex vivo model presents a promising template for chemoembolization evaluation before in vivo experiments for the development of novel embolic agents.

Hepatic Artery Infusion Chemotherapy Using Fluorouracil, Leucovorin, and Oxaliplatin versus Transarterial Chemoembolization as Initial Treatment for Locally Advanced Hepatocellular Carcinoma: A Propensity Score-Matching Analysis

PURPOSE

To compare the efficacy and safety of hepatic arterial infusion chemotherapy (HAIC) with a modified fluorouracil, leucovorin, and oxaliplatin (mFOLFOX) regimen with that of transarterial chemoembolization as a locoregional treatment for patients with locally advanced hepatocellular carcinoma (HCC).

METHODS

This retrospective study included adult patients with locally advanced HCC who received first-line treatment with either HAIC-mFOLFOX or conventional transarterial chemoembolization monotherapy from January 2015 to December 2016. The outcomes, including tumor response rates, evaluated via imaging assessment using the modified response evaluation criteria in solid tumors; overall survival; progression-free survival; and safety, were compared. The propensity score-matching methodology was used to reduce the influence of confounding factors on the outcomes.

RESULTS

The study included 131 patients with locally advanced HCC who underwent transarterial chemoembolization and 101 who received HAIC-mFOLFOX as initial treatment. After propensity score matching (n = 67 in each group), patients who received HAIC-mFOLFOX had a higher objective response rate (43.3% vs 13.4%, P = .001), longer median overall survival (13.9 vs 6.0 months, P < .001), and longer median progression-free survival (6.4 vs 2.8 months, P = .001) than those who underwent transarterial chemoembolization. The survival benefit with HAIC-mFOLFOX was strengthened in patients with HCC with vascular invasion (hazard ratio: 0.379; 95% confidence interval: 0.237-0.607). HAIC-mFOLFOX was associated with lower incidences of severe adverse events (8.9% vs 22.9%) and liver toxicity than transarterial chemoembolization.

CONCLUSIONS

Compared with transarterial chemoembolization, HAIC-mFOLFOX is a potentially safer and more effective locoregional therapy for patients with locally advanced HCC.

A review of applying transarterial chemoembolization (TACE) method for management of hepatocellular carcinoma

Liver cancer is one of the most ordinary reasons for death among cancers. Hepatocellular carcinoma (HCC) is the most common type of liver cancer. In spite of the fact that various remedial methods have been approved particularly the survival effects of the transcatheter arterial chemoembolization (TACE) method have been accomplished widely in the HCC treatment. By applying the TACE method correctly, good survival outcomes can be achieved without harmfully affecting the hepatic functions. Transarterial chemoembolization mixes the effect of avascular necrosis (AVN) with the effect of regional chemotherapy those are under the influence of arterial embolization. By knowing the fact that the metastases of liver cancer and also perfusion indices in hepatocellular carcinoma (HCC) are via hepatic arteries, doctors chose the TACE method for the treatment of liver cancer. On the other hand, in this method, the radiologists can easily convey antitumor remedies via the arteries. Anyway, medium-level HCC is a sensitive stage of the heterogeneous disease that many patients suffer from, so specialists must consider it as a hazardous syndrome. The TACE procedure could be applied just in cases that the liver function of patients is appropriate yet, the patient liver portal vein do not have any problems and the patients do not have ascites disorder. This review is aimed to figure out the evident advantages of TACE especially by a comprehensive view on the medium level HCC. Because of that this treatment method is suggested as a first-line remedy. At last, the future landscape of the initial factors of research in managing HCC disorders have been summarized.

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.

Ultraselective conventional transarterial chemoembolization: When and how?

Ultraselective conventional transarterial chemoembolization (cTACE), defined as cTACE at the most distal portion of the subsubsegmental hepatic artery, is mainly performed for hepatocellular carcinoma (HCC) ≤5 cm. Distal advancement of a microcatheter enables injection of a larger volume of iodized oil into the portal vein in the limited area under non-physiological hemodynamics. As a result, the reversed portal flow into the tumor through the drainage route of the tumor that occurs when the hepatic artery is embolized is temporarily blocked. By adding gelatin sponge slurry embolization, both the hepatic artery and portal vein are embolized and not only complete necrosis of can be achieved. Ultraselective cTACE can cure small HCCs including less hypervascular tumor portions and replace surgical resection and radiofrequency ablation in selected patients.

Biodegradable Pickering emulsions of Lipiodol for liver trans-arterial chemo-embolization

Water-in-oil (W/O) Lipiodol emulsions remain the preferable choice for local delivery of chemotherapy in the treatment of hepatocellular carcinoma. However, their low stability severely hampers their efficiency. Here, remarkably stable W/O Lipiodol emulsion stabilized by biodegradable particles was developed thanks to Pickering technology. The addition of poly(lactide-co-glycolide) nanoparticles (NPs) into the aqueous-phase of the formulation led to W/O Pickering emulsion by a simple emulsification process through two connected syringes. Influence of nanoparticles concentration and water/oil ratio on emulsion stability and droplet size were studied. All formulated Pickering emulsions were W/O type, stable for at least one month and water droplets size could be tuned by controlling nanoparticle concentration from 24 µm at 25 mg/mL to 69 µm at 5 mg/mL. The potential of these emulsions to efficiently encapsulate chemotherapy was studied through the internalization of doxorubicin (DOX) into the aqueous phase with a water/oil ratio of 1/3 as recommended by the medical community. Loaded-doxorubicin was released from conventional emulsion within a few hours whereas doxorubicin from stable Pickering emulsion took up to 10 days to be completely released. In addition, in vitro cell viability evaluations performed on the components of the emulsion and the Pickering emulsion have shown no significant toxicity up to relatively high concentrations of NPs (3 mg/mL) on two different cell lines: HUVEC and HepG2. STATEMENT OF SIGNIFICANCE: We present an original experimental research in the field of nanotechnology for biomedical applications. In particular, we have formulated, thanks to Pickering technology, a new therapeutic emulsion stabilized with biodegradable PLGA nanoparticles. As far as we know, this is the first therapeutic Pickering emulsion reported in the literature for hepatocellular carcinoma. Such a new emulsion allows to easily prepare a predictable and stable lipiodolized emulsion having all the required characteristics for optimum tumor uptake. As demonstrated throughout our manuscript, emulsions stabilized with these nanoparticles have the advantage of being biodegradable, biocompatible and less toxic compared to usual emulsions stabilized with synthetic surfactants. These findings demonstrate the plausibility of the use of Pickering emulsions for chemoembolization as a therapeutic agent in extended release formulations.

Softness Induced Enhancement in Net Throughput of Non-Linear Bio-Fluids in Nanofluidic Channel under EDL Phenomenon

In this article, we describe the electro-hydrodynamics of non-Newtonian fluid in narrow fluidic channel with solvent permeable and ion-penetrable polyelectrolyte layer (PEL) grafted on channel surface with an interaction of non-overlapping electric double layer (EDL) phenomenon. In this analysis, we integrate power-law model in the momentum equation for describing the non-Newtonian rheology. The complex interplay between the non-Newtonian rheology and interfacial electrochemistry in presence of PEL on the walls leads to non-intuitive variations in the underlying flow dynamics in the channels. As such, we bring out the variations in flow dynamics and their implications on the net throughput in the channel in terms of different parameters like power-law index (n), drag parameter (α), PEL thickness (d) and Debye length ratio (κ/κ_PEL) are discussed. We show, in this analysis, a relative enhancement in the net throughput through a soft nanofluidic channel for both the shear-thinning and shear-thickening fluids, attributed to the stronger electrical body forces stemming from ionic interactions between polyelectrolyte layer and electrolyte layer. Also, we illustrate that higher apparent viscosity inherent with the class of shear-thickening fluid weakens the softness induced enhancement in the volumetric flow rate for the shear-thickening fluids, since the viscous drag offered to the f low f ield becomes higher for the transport of shear-thickening fluid.

Development of pumping emulsification device with glass membrane to form ideal lipiodol emulsion in transarterial chemoembolization

PURPOSE

To evaluate a pumping emulsification device that can improve the physiochemical properties and stability of lipiodol emulsion for conventional transarterial chemoembolization.

MATERIALS AND METHODS

A pumping emulsification device constructed of a glass membrane with a hydrophobic surface with pore size of 50 μm in diameter was placed between two syringe adaptors. Epirubicin solutions were mixed with lipiodol with pumping exchanges using the emulsification device or a three-way cock. The ratios of epirubicin solution to lipiodol were 1:2 or 1:1. A total of 120 emulsions were created.

RESULTS

The emulsification device showed significantly higher percentages of water-in-oil when compared with the three-way cock (97.9 % vs. 68.9 % in 1:2 ratio, and 82.1 % vs. 17.8 % in 1:1 ratio, p < .001). Droplet sizes in the emulsification device were more homogenous. Mean droplet sizes and viscosities in the emulsification device did not show any significant changes for 30 min after pumping, whereas in the three-way cock, the droplet sizes significantly enlarged and viscosities significantly decreased (p=.023 and p=.002).

CONCLUSION

The emulsification device can form a high percentage of water-in-oil emulsion with stable droplets sizes and viscosities. This developed device is promising to increase therapeutic effects in conventional transarterial chemoembolization.

KEY POINTS

• We developed new device for transarterial chemoembolization for liver cancer. • The device can improve the physiochemical properties of lipiodol emulsion. • The device can increase the therapeutic effects in conventional transarterial chemoembolization.

Techniques to Form a Suitable Lipiodol-Epirubicin Emulsion by Using 3-Way Stopcock Methods in Transarterial Chemoembolization for Liver Tumor

PURPOSE

To compare physicochemical properties of emulsions of ethiodized oil (Lipiodol; Guerbet, Villepinte, France) and epirubicin prepared using different techniques for conventional transarterial chemoembolization.

MATERIALS AND METHODS

Lipiodol was mixed with epirubicin solution (8.33 mg/mL) by using a 3-way stopcock. The following technical parameters were compared: ratio of epirubicin solution to Lipiodol (1:2 vs 1:1), number of pumping exchanges through the stopcock (20 exchanges vs 10 exchanges), pumping speed (1 s/push vs 2 s/push), and first push syringe (epirubicin solution vs Lipiodol).

RESULTS

The mean percentage of water-in-oil was 70.45 ± 1.51 in the 1:2 epirubicin-Lipiodol ratio and 16.03 ± 2.95 in the 1:1 ratio (P < .001). The first push syringe did not influence emulsion type. Median droplet sizes were significantly larger in the slower pumping speed (52.0 μm in 2 s vs 33.7 μm in 1 s; P < .001), whereas there was no significant difference in number of pumping exchanges. Droplet sizes enlarged during 30 minutes after pumping. Viscosity was lower in the 1:1 ratio and the slower pumping speed. Viscosity decreased during 30 minutes after pumping.

CONCLUSIONS

The ratio of epirubicin to Lipiodol is a significant factor to form water-in-oil emulsions with higher viscosity. The percentage of water-in-oil is limited to 70% using current pumping techniques. The pumping speed strongly influences droplet size and viscosity.

Performance of novel virtual parenchymal perfusion software visualizing embolized areas of transcatheter arterial chemoembolization for hepatocellular carcinoma

AIM

To evaluate the performance of novel virtual parenchymal perfusion (VPP) software in conventional transcatheter arterial chemoembolization (cTACE) for hepatocellular carcinoma.

METHODS

VPP was retrospectively applied to 43 hepatocellular carcinomas treated with cTACE. The virtual embolized area (VEA) was estimated after positioning a virtual injection point on images of non-selective cone-beam computed tomography during hepatic arteriography, at the same position in superselective cTACE. The real embolized area (REA) was defined as the area where iodized oil was retained on 1-week computed tomography after cTACE. Three dimensions across the tumor (maximum [a] and minimum [b] in the axial and craniocaudal [c]) directions, and the volume of the VEA and REA were compared using linear regression analysis. It was also evaluated whether an adequate safety margin ≥5 mm could be predicted by VPP.

RESULTS

The mean lengths of a, b, and c of the VEA and REA were 54.6 ± 15.9 mm (range 24.9-91.0 mm) and 55.0 ± 15.7 mm (range 23.9-92.8 mm; r = 0.9448, P < 0.001), 35.4 ± 11.7 mm (range 16.1-66.0 mm) and 35.4 ± 13.2 mm (range 12.2-69.2 mm; r = 0.9369, P < 0.001), and 42.1 ± 11.6 mm (range 25.0-75.7 mm) and 42.9 ± 11.7 mm (range 25.7-78.7 mm; r = 0.9092, P < 0.001), respectively. The mean volume of the VEA and REA was 71.8 ± 44.8 mL and 75.5 ± 46.9 mL, respectively (r = 0.9913, P < 0.0001). VPP showed no safety margins in seven tumors, including all three actually embolized without safety margins.

CONCLUSION

The VEA estimated using VPP showed a good correlation with the REA of cTACE.

Superselective Conventional Transarterial Chemoembolization for Hepatocellular Carcinoma: Rationale, Technique, and Outcome

Conventional transarterial chemoembolization with ethiodized oil and gelatin sponge (GS) particles is a standard technique for hepatocellular carcinoma. Ethiodized oil can temporarily block tumor sinusoids, portal venules, hepatic sinusoids, and arterial microcommunications. By adding GS embolization, strong ischemic effects not only on the tumor but also on the surrounding liver parenchyma can be achieved. Superselective conventional transarterial chemoembolization is mainly indicated for patients with Child-Pugh scores of 5-8, tumors ≤ 7 cm, and ≤ 5 lesions. According to a Japanese nationwide survey, the 5-year survival rate of patients with Child-Pugh class A and a single tumor was 52%.

Temporal variations in stump pressure and assessment of images obtained from cone-beam computed tomography during balloon-occluded transarterial chemoembolization

AIM

Balloon-occluded transcatheter arterial chemoembolization (B-TACE) was used to show the optimized duration of balloon occlusion to start injection of lipiodol in order to maximize lipiodol deposition in the nodule, and to reveal the endpoint of lipiodol injection.

METHODS

Of 29 consecutive patients who underwent balloon-occluded TACE between November 2013 and February 2014, we were able to measure stump pressure for 219 nodules in 27 patients. Tumors were counted, measured and could be visually assessed in 20 of these patients at 26 sites. Tumors with multiple feeders were found in eight patients. Arterial blood pressure was measured before, immediately after and 5 min after balloon occlusion prior to intra-arterial injection, as well as before and after balloon deflation after intra-arterial injection. Images were assessed qualitatively by two radiologists as well as quantitatively by calculating the contrast-to-noise ratio.

RESULTS

We found no significant difference in pressure between immediately after and 5 min after balloon occlusion. Mean stump pressure before balloon deflation after intra-arterial injection was 70.4 mmHg. We observed a significant increase in qualitative scores after balloon occlusion (P < 0.001), and the mean score in the third-order branch was significantly higher than that in the first-order branch (P = 0.048).

CONCLUSION

Our results indicate that intra-arterial injection can be started at any time after balloon occlusion and that 70 mmHg may be considered as a possible indicator of the end-point for arterial injection.

Selective balloon-occluded transarterial chemoembolization for patients with one or two hepatocellular carcinoma nodules: Retrospective comparison with conventional super-selective TACE

AIM

Selective balloon-occluded transarterial chemoembolization (B-TACE) enables strong TACE; infusion of more volume of lipiodol emulsion and forceful injection of embolization materials. The aim of this study is to analyze the efficacy of B-TACE for patients with one or two hepatocellular carcinoma (HCC) nodules compared with conventional super-selective TACE using a microcatheter (C-TACE).

METHODS

We retrospectively selected patients without previous history of TACE, with one or two HCC nodules, with performance status 0/1, and with liver function of Child-Pugh score A/B. Between 2008 and 2010, a 3-Fr microballoon catheter was used for targeted TACE (B-TACE group). Between 2005 and 2008, a 2-Fr microcatheter was used (C-TACE group). Control rates of primary nodule, overall survival rates and tumor-free rates in the liver were calculated for each group using the Kaplan-Meier method. Univariate analysis was performed to compare between the groups using the log-rank test. Multivariate analysis was performed for analysis of prognostic factors using Cox's proportional hazard model. The factors were B-TACE versus C-TACE, Child-Pugh score A versus B, single nodule versus double, large nodule versus small , elder versus not, and prior radiofrequency ablation treatment versus not.

RESULTS

Control rates of the primary nodule were improved by B-TACE. B-TACE was an independent factor to improve both control rates of the primary nodule and overall survival rates. Child-Pugh score A was an independent factor to increase overall survival rates. There was no statistically significant difference in overall survival or tumor-free survival rates between the groups.

CONCLUSION

B-TACE was an independent factor to improve overall survival rates on multivariate analysis, but there was no significant difference in overall survival rates between B-TACE and C-TACE groups on univariate analysis.

Three-dimensional reconstruction of a vascular network by dynamic tracking of magnetite nanoparticles

PURPOSE

Visualization of small blood vessels feeding tumor sites provides important information on the tumors and their microenvironment. This information plays an important role in targeted drug therapies using magnetic gradients. However, capabilities of current clinical imaging modalities may be insufficient to resolve complex microvascular networks. The purpose of this study is to map the vascular network, 3D, based on the magnetic susceptibility contrast.

METHODS

Magnetic particles induce an inhomogeneity in the MRI's magnetic field in an order much larger than their real size. This is an approach to compensate the spatial resolution insufficiency of a clinical MR scanner. Micron-sized agglomerations of magnetite nanoparticles were injected in a 3D phantom vascular network, and a fast multislice, multiacquisition MR sequence was applied to track the agglomerations along their trajectories. The experiment was performed twice for two different imaging planes: coronal and transversal. The susceptibility artifact in the images indicated the presence and the position of the agglomerations. The calculated positions through multiple images were assembled to build up the 3D distribution of the vascular network.

RESULTS

The calculated points were compared with the centerline of the channels, extracted from the 3D reference image, to determine the absolute measurement error. The mean error was measured to be approximately half of the pixel's size. It was found that the positioning error on the axis perpendicular to the imaging slice was nearly twice as high as on the imaging plane axes due to the slice thickness. In order to compensate for the lack of resolution on the perpendicular axis, the reconstruction was performed using a combination of coronal and transversal data. The combination of the coordinates led to a significant decrease in the mean measurement error at each segment in the vascular network (p < 0.001).

CONCLUSIONS

A method for 3D reconstruction of a microvascular network based on the susceptibility contrast in MRI and using a clinical scanner and a commercial receiver coil was proposed. The method presents a novel approach for reconstruction of vascular networks using the susceptibility effect. The proposed method may be applied to resolve vascular networks at a micrometric scale.

Locoregional therapy of hepatocellular carcinoma

Hepatocellular carcinoma can be treated using minimally invasive, image-guided, catheter-based or percutaneous techniques. Such procedures offer compelling clinical outcomes with a favorable side-effect profile in a population of patients who are poor candidates for surgical or systemic treatment. This article discusses key data regarding the effectiveness of locoregional therapies in treating these patients. Disease-specific treatment is discussed in the context of hepatocellular carcinoma, with additional data discussed in the context of transplantation. As rapid innovation occurs in the realm of oncology, interventional oncology represents a safe, effective alternative that continues to generate impressive data that could potentially change treatment paradigms.

Interventional treatment for unresectable hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common cancer and third leading cause of cancer-related death in the world. The Barcelona clinic liver cancer classification is the current standard classification system for the clinical management of patients with HCC and suggests that patients with intermediate-stage HCC benefit from transcatheter arterial chemoembolization (TACE). Interventional treatments such as TACE, balloon-occluded TACE, drug-eluting bead embolization, radioembolization, and combined therapies including TACE and radiofrequency ablation, continue to evolve, resulting in improved patient prognosis. However, patients with advanced-stage HCC typically receive only chemotherapy with sorafenib, a multi-kinase inhibitor, or palliative and conservative therapy. Most patients receive palliative or conservative therapy only, and approximately 50% of patients with HCC are candidates for systemic therapy. However, these patients require therapy that is more effective than sorafenib or conservative treatment. Several researchers try to perform more effective therapies, such as combined therapies (TACE with radiotherapy and sorafenib with TACE), modified TACE for HCC with arterioportal or arteriohepatic vein shunts, TACE based on hepatic hemodynamics, and isolated hepatic perfusion. This review summarizes the published data and data on important ongoing studies concerning interventional treatments for unresectable HCC and discusses the technical improvements in these interventions, particularly for advanced-stage HCC.

Comparison of the antitumor efficacy of transcatheter arterial chemoembolization with a miriplatin-iodized oil suspension and a cisplatin-iodized oil suspension for hepatocellular carcinoma

AIM

To retrospectively compare the short-term antitumor efficacy and safety of transcatheter arterial chemoembolization (TACE) with a cisplatin-iodized oil suspension (C-IS) and a miriplatin-iodized oil suspension (M-IS) for hepatocellular carcinoma (HCC).

METHODS

Of patients who underwent TACE for unresectable HCC between January 2010 and August 2011, 25 and 21 patients received C-IS and M-IS, respectively. The short-term therapeutic efficacy of both groups was evaluated by the treatment effect seen on dynamic enhanced computed tomography or magnetic resonance imaging of tumor nodules 3 months after treatment. Adverse events were evaluated to compare C-IS and M-IS.

RESULTS

After TACE using C-IS and M-IS, 100% necrosis or tumor size reduction was achieved in 30 and 18 tumor nodules, respectively (81% vs 53%; P = 0.006). Objective responses were achieved in 30 nodules exposed to TACE using C-IS and 17 exposed to TACE using M-IS (81% vs 50%; P = 0.011). Disease control was achieved in 36 nodules exposed to C-IS and 27 exposed to M-IS (97% vs 79%; P = 0.017). The percentage of patients attaining a complete response, an objective response and disease control was significantly greater in the C-IS group than in the M-IS group. No significant differences were found in the aspartate aminotransferase, alanine aminotransferase, total bilirubin and creatinine levels between the two groups either before treatment or 1 month after treatment.

CONCLUSION

The short-term antitumor effects of TACE with C-IS may be superior to those with M-IS in terms of the complete response, objective response and disease control rates.

What Is the Most Effective Drug Delivery System for Cisplatin during the Treatment of Hepatic Tumors with Single-Session Transcatheter Chemotherapy? A Pilot Study

Background/Aims

The aim of this study was to determine the pharmacodynamics of cisplatin following three different treatment procedures for intrahepatic arterial infusion therapy for hepatocellular carcinoma (HCC).

Methods

We divided 13 HCC patients into the following three groups: group A, lone injection of cisplatin (n=3); group B, combined injection of cisplatin and lipiodol, with embolization using small gelatin cubes (GCs) (n=5); and group C, injection of suspended lipiodol with cisplatin powder, with embolization using small GCs (n=5). In each group, the free cisplatin concentration in the hepatic vein was measured at 0, 5, 10, and 30 minutes.

Results

The mean free cisplatin concentrations were as follows. For group A, the mean was 48.58 µg/mL at 0 minute, 7.31 µg/mL at 5 minutes, 5.70 µg/mL at 10 minutes, and 7.15 µg/mL at 30 minutes. For the same time points, for group B, the concentrations were 8.66, 4.23, 3.22, and 1.65 µg/mL, respectively, and for group C, the concentrations were 4.81, 2.61, 2.52, and 1.75 µg/mL, respectively. The mean area under the curve (AUC)_0-infinity for the free cisplatin concentration was 7.80 in group A, 2.48 in group B, and 2.27 in group C. The AUC_0-infinity for the free cisplatin concentration gradually decreased, from group A to group C.

Conclusions

These results indicate that the combination of lipiodol and small GCs may be useful for delaying cisplatin drainage from the liver.

Transcatheter arterial chemoembolization based on hepatic hemodynamics for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common cancer and the third leading cause of cancer-related deaths in the world. The Barcelona Clinic Liver Cancer (BCLC) classification has recently emerged as the standard classification system for clinical management of patients with HCC. According to the BCLC staging system, curative therapies (resection, transplantation, and percutaneous ablation) can improve survival in HCC patients diagnosed at an early stage and offer potential long-term curative effects. Patients with intermediate-stage HCC benefit from transcatheter arterial chemoembolization (TACE), and those diagnosed at an advanced stage receive sorafenib, a multikinase inhibitor, or conservative therapy. Most patients receive palliative or conservative therapy only, and approximately 50% of patients with HCC are candidates for systemic therapy. TACE is often recommended for advanced-stage HCC patients all over the world because these patients desire therapy that is more effective than systemic chemotherapy or conservative treatment. This paper aims to summarize both the published data and important ongoing studies for TACE and to discuss technical improvements in TACE for advanced-stage HCC.

Dense accumulation of lipiodol emulsion in hepatocellular carcinoma nodule during selective balloon-occluded transarterial chemoembolization: measurement of balloon-occluded arterial stump pressure

PURPOSE

To reveal the mechanism of dense accumulation of lipiodol emulsion (LE) in hepatocellular carcinoma (HCC) during selective balloon-occluded transarterial chemoembolization (B-TACE).

METHODS

Balloon-occluded arterial stump pressure (BOASP) at the embolization portion was measured during selective B-TACE for 43 nodules in 42 patients. Fluoroscopy and digital subtraction angiography were prospectively observed during selective B-TACE to note whether dense LE accumulation in HCC occurred. The LE concentration ratio of HCC to embolized liver parenchyma (LECHL ratio) was also calculated for each treatment on the basis of the computed tomographic scan obtained immediately after selective B-TACE. The relationships between degree of LE accumulation and the BOASP, as well as the LECHL ratio, were analyzed.

RESULTS

Arterial flow beyond the catheter tip was maintained even after balloon inflation. In 39 of 43 treatments, LE inflow into the nontumorous liver parenchyma ceased immediately after LE droplets were filled in arteries of the nontumorous liver parenchyma while LE inflow into the HCC nodule continued (group 1). More dense LE accumulation in HCC nodule was obtained in these 39 treatments. In four treatments, LE inflow both into the nontumorous liver parenchyma and into the HCC nodule continued, and no dense LE accumulation in HCC nodule was observed (group 2). In these four treatments, thick anastomotic vessels with collateral artery were noted. The BOASP in group 1 was (mean ± SD) 33.8 ± 12.8 mmHg (range 13-64 mmHg) and that in group 2 was 92.3 ± 7.4 mmHg (range 83-100 mmHg). There was a statistically significant difference in BOASP between groups (p = 0.00004, Welch's t test). The LECHL ratio in group 1 was 18.3 ± 13.9 (range 2.9-54.2) and that in group 2 was 2.6 ± 1.1 (range 1.7-4.2). There was a statistically significant difference in the LECHL ratio between the groups (p = 0.000034, Welch's t test).

CONCLUSION

Selective B-TACE induced dense LE accumulation in HCC nodules in 39 (91 %) of 43 treatments in which BOASP was 64 mmHg or less.

Comparative study of cisplatin-iodized oil suspension and emulsion for transcatheter arterial chemoembolization of rabbit VX2 liver tumors

AIM

  To evaluate the antitumor effects and hepatotoxicity of transcatheter arterial chemoembolization (TACE) with cisplatin-iodized oil suspension and emulsion in a rabbit tumor model.

METHODS

  Transcatheter arterial chemoembolization was performed on 12 rabbits with hepatic VX2 tumors using a cisplatin suspension (1 mg/kg cisplatin and 0.1 mL/kg iodized oil, n = 6) or emulsion (1 mg/kg cisplatin, 0.1 mL/kg of iodized oil, and 0.1 mL/kg saline solution, n = 6). Time series changes in plasma platinum concentration were compared over 24 h. All rabbits were killed at 7 days after TACE, and the growth ratio and residual viable proportion of tumors were calculated on the basis of ultrasonographic and histopathological findings. Hepatotoxicity was also evaluated. Differences between the two groups were statistically assessed with the Mann-Whitney U-test. The animal care committee of our institute approved this study.

RESULTS

  Plasma platinum concentrations were significantly higher in the suspension group than in the emulsion group at 0.5-24 h after TACE (P < 0.05). Growth ratios (-24.6 ± 9.98% vs. 21.4 ± 8.87%, respectively; P = 0.004) and residual viable proportions of tumors (25.8 ± 5.02% vs. 51.1 ± 11.4%, respectively; P = 0.009) were significantly lower in the suspension group than in the emulsion group. Hepatotoxicity was transient in all rabbits.

CONCLUSION

  Cisplatin-iodized oil suspensions facilitated the slow release of cisplatin at the tumor border. A suspension is preferable to an emulsion for drug delivery and the antitumor effect during the treatment of VX2 liver tumors with TACE.

Comparison of epirubicin-iodized oil suspension and emulsion for transcatheter arterial chemoembolization in VX2 tumor

To compare the antitumor efficacy and safety of transcatheter arterial chemoembolization (TACE) by epirubicin suspension (epirubicin suspension: epirubicin-iodized oil mixture without solution) to that by epirubicin emulsion (epirubicin emulsion: epirubicin-iodized oil mixture with solution), the efficacy of treatment by administration of either an epirubicin suspension or emulsion was examined in an animal model. Changes in plasma epirubicin concentration were compared over 24 h immediately after treatment, and enhanced ultrasonographic and histopathological analysis subsequently conducted 7 days after treatment to determine the growth ratio and proportion of viable tumor cells. The growth ratio and proportion of viable tumor cells were found to be significantly lower in the suspension group than in the emulsion group while the plasma epirubicin concentration was found to be significantly higher in the suspension group than in the emulsion group. These results indicate that administration of an epirubicin suspension is a superior form of TACE compared to that of administration of an epirubicin emulsion.

Comparison of local control effects of superselective transcatheter arterial chemoembolization using epirubicin plus mitomycin C and miriplatin for hepatocellular carcinoma

PURPOSE

To compare local control effects of superselective transcatheter arterial chemoembolization (TACE) using epirubicin (EPI) plus mitomycin C (M) and miriplatin (MPT) for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

One-hundred and twenty-nine HCCs treated with superselective TACE were divided into three groups according to the type of anticancer drug; EPI-M-TACE (n = 51), MPT-TACE (n = 21), and MPT-I-TACE (MPT emulsion) (n = 57). Local recurrence, patterns of recurrence (intratumoral recurrence; IR), and follow-up angiograms were evaluated.

RESULTS

Mean tumor diameter and follow-up period for the EPI-M-TACE, MPT-TACE, and MPT-I-TACE groups were 16.9 mm and 15.5 months, 20.7 mm and 12.0 months, and 18.8 mm and 9.6 months, respectively. Local recurrence for the EPI-M-TACE, MPT-TACE, and MPT-I-TACE groups at 5, 10, and 15 months was 6.1, 47.6, and 40.1%, 23.5, 67.3, and 63.9%, and 26.2, 75.4, and 72.9%, respectively. IR for the EPI-M-TACE, MPT-TACE, and MPT-I-TACE groups was 23.1, 71.4, and 71.0%, respectively. Local recurrence and IR in the EPI-M-TACE group were significantly less than those in the MPT-TACE and MPT-I-TACE groups. Follow-up angiograms revealed less arterial damage in the MPT-TACE and MPT-I-TACE groups.

CONCLUSION

Superselective TACE using MPT resulted in very frequent local recurrence, in particular IR, despite less arterial damage.