Pharmacokinetics and Early Tumor Response to Conventional Transarterial Chemoembolization with Sorafenib and Doxorubicin in a VX2 Rabbit Tumor Model.

PURPOSE: To investigate the pharmacokinetics (PK) and early effects of conventional transarterial chemoembolization (TACE) using sorafenib and doxorubicin on tumor necrosis, hypoxia markers, and angiogenesis in a rabbit VX2 liver tumor model. MATERIALS AND METHODS: VX2 tumor-laden New Zealand White rabbits (N = 16) were divided into 2 groups: 1 group was treated with hepatic arterial administration of ethiodized oil and doxorubicin emulsion (DOX-TACE), and the other group was treated with ethiodized oil, sorafenib, and doxorubicin emulsion (SORA-DOX-TACE). Animals were killed within 3 days of the procedure. Levels of sorafenib and doxorubicin were measured in blood, tumor, and adjacent liver using mass spectrometry. Tumor necrosis was determined by histopathological examination. Intratumoral hypoxia-inducible factor (HIF) 1α, vascular endothelial growth factor (VEGF), and microvessel density (MVD) were determined by immunohistochemistry. RESULTS: The median intratumoral concentration of sorafenib in the SORA-DOX-TACE group was 17.7 µg/mL (interquartile range [IQR], 7.42-33.5 µg/mL), and its maximal plasma concentration (Cmax) was 0.164 µg/mL (IQR, 0.0798-0.528 µg/mL). The intratumoral concentration and Cmax of doxorubicin were similar between the groups: 4.08 µg/mL (IQR, 3.18-4.79 µg/mL) and 0.677 µg/mL (IQR, 0.315-1.23 µg/mL), respectively, in the DOX-TACE group and 1.68 µg/mL (IQR, 0.795-4.08 µg/mL) and 0.298 µg/mL (IQR, 0.241-0.64 µg/mL), respectively, in the SORA-DOX-TACE group. HIF-1α expression was increased in the SORA-DOX-TACE group than in the DOX-TACE group. Tumor volume, tumor necrosis, VEGF expression, and MVD were similar between the 2 groups. CONCLUSIONS: The addition of sorafenib to DOX-TACE delivered to VX2 liver tumors resulted in high intratumoral and low systemic concentrations of sorafenib without altering the PK of doxorubicin.

Characterization of an Inducible Alcoholic Liver Fibrosis Model for Hepatocellular Carcinoma Investigation in a Transgenic Porcine Tumorigenic Platform.

PURPOSE: This study used the Oncopig Cancer Model (OCM) to develop alcohol-induced fibrosis in a porcine model capable of developing hepatocellular carcinoma. MATERIALS AND METHODS: Liver injury was induced in 8-week-old Oncopigs (n = 10) via hepatic transarterial infusion of 0.75 mL/kg ethanol-ethiodized oil (1:3 v/v). Feasibility was assessed in an initial Oncopig cohort (n = 5) by histologic analysis at 8 weeks after induction, and METAVIR results were compared to age- and sex-matched healthy controls (n = 5). Liver injury was then induced in a second OCM cohort (n = 5) for a time-course study, with post-induction disease surveillance via biweekly physical exam, lab analysis, and liver biopsies until 20 weeks after induction. RESULTS: In Cohort 1, 8-week post-induction liver histologic analysis revealed median METAVIR F3 (range, F3-F4) fibrosis, A2 (range, A2-A3) inflammation, and 15.3% (range, 5.0%-22.9%) fibrosis. METAVIR and inflammation scores were generally elevated compared to healthy controls (F0-F1, P = 0.0013; A0-A1, P = .0013; median percent fibrosis 8.7%, range, 5.8%-12.1%, P = .064). In Cohort 2, histologic analysis revealed peak fibrosis severity of median METAVIR F3 (range, F2-F3). However, lack of persistent alcohol exposure resulted in liver recovery, with median METAVIR F2 (range, F1-F2) fibrosis at 20 weeks after induction. No behavioral or biochemical abnormalities were observed to indicate liver decompensation. CONCLUSIONS: This study successfully validated a protocol to develop METAVIR F3-F4 fibrosis within 8 weeks in the OCM, supporting its potential to serve as a model for hepatocellular carcinoma in a fibrotic liver background. Further investigation is required to determine if repeated alcohol liver injury is required to develop an irreversible METAVIR grade F4 porcine cirrhosis model.

Mechanism of Action, Pharmacokinetics, Efficacy, and Safety of Transarterial Therapies Using Ethiodized Oil: Preclinical Review in Liver Cancer Models.

PURPOSE: To systematically review mechanism of action, pharmacokinetics (PKs), efficacy, and safety of ethiodized oil-based locoregional therapy (LRT) for liver cancer in preclinical models. MATERIALS AND METHODS: A MEDLINE search was performed from 1988 to 2016. Search terms included hepatocellular carcinoma (HCC), HCC, liver-cell carcinoma, liver, hepatic, hepatocarcinoma, transarterial or chemoembolization, TACE, animal, Lipiodol, Ethiodol, iodized oil, and/or poppy-seed oil. Inclusion criteria were: publication in a peer-reviewed journal, an accepted animal model, and PK/safety/efficacy data reported. Exclusion criteria were: inadequate PK, safety, or efficacy data; anticancer drug name/dose not available; and article not in English. Outcomes included intratumoral anticancer drug uptake, PKs, tolerance, tumor response, and survival. RESULTS: Of 102 identified articles, 49 (49%) met the inclusion criteria. Seventeen, 35, and 2 articles used rat, rabbit, and pig models. Mechanism of action was investigated in 11 articles. Eleven articles reported drug uptake, PK, and tolerance data, showing 0.5%-9.5% of injected chemotherapy dose in tumor. Tumor-to-liver drug distribution ratios were 2-157. Toxicology data across 6 articles showed transient liver laboratory level elevations 1 day after LRT. There was no noteworthy liver or extrahepatic histologic damage. Nine articles reported tumor response, with 0%-30% viable tumor and -10% to -38% tumor growth at 7 days after LRT. Two articles reported survival, showing significantly longer survival after LRT vs untreated controls (56/60 d vs 33/28 d). Several articles described ethiodized oil mixed with radiopharmaceutical (n = 7), antiangiogenic (n = 6), gene (n = 6), nanoembolic (n = 5), immune (n = 2), or other novel (n = 1) agents. CONCLUSIONS: Animal studies show preferential tumor uptake of anticancer agent, good hepatic/systemic tolerance, high tumor response, and enhanced survival after ethiodized oil-based LRT.

Correlation of Doxorubicin Delivery and Tumor Necrosis after Drug-eluting Bead Transarterial Chemoembolization of Rabbit VX2 Liver Tumors.

Purpose To quantify the correlation between doxorubicin (DOX) delivery and tumor necrosis after drug-eluting bead (DEB) transarterial chemoembolization (TACE). Materials and Methods In this animal care committee-approved study, New Zealand white rabbit VX2 liver tumors were treated transarterially with DOX-loaded 70-150-µm DEBs in five treatment groups with varying drug doses: sham (saline), 0 mg, 12.5 mg, 25 mg, and 37.5 mg. DEB TACE was followed by 3- and 7-day sacrifice, tumor harvest, and sectioning. Drug delivery was assessed by using fluorescence imaging, and tumor necrosis was quantified by means of histologic analysis. Statistical correlation of DOX delivery and tumor necrosis was performed by using the Spearman rank correlation coefficient (ρ). Results Thirty-six VX2 tumors (median diameter, 1.3 cm) in 20 rabbits (median weight, 2.8 kg) underwent successful DEB TACE. Treatment groups included eight, seven, eight, five, and eight tumors of similar size (P > .05). Tumors showed progressively greater DOX extent (sham, 0%; 0 mg, 0%; 12.5 mg, 3%; 25 mg, 20%; and 37.5 mg, 27%) and intensity (sham, 0.4; 0 mg, 1.9; 12.5 mg, 8.5; 25 mg, 9.6; and 37.5 mg, 18.3) and higher median percentage necrosis (sham, 68%; 0 mg, 64%; 12.5 mg, 76%; 25 mg, 78%; and 37.5 mg, 83%) across DOX treatment groups. Correlation of DOX extent (ρ = 0.975, P = .005) and intensity (ρ = 0.900, P = .037) with percentage tumor necrosis was statistically significant. Conclusion Incremental increases in DOX correlate with greater necrosis in rabbit VX2 liver tumors after DEB TACE. This result indicates an essential role for chemotherapy-induced cytotoxicity in TACE effectiveness and supports the use of chemotherapeutic drugs in transarterial therapy. (©) RSNA, 2016 Online supplemental material is available for this article.

Conventional Ethiodized Oil Transarterial Chemoembolization for Treatment of Hepatocellular Carcinoma: Contemporary Single-Center Review of Clinical Outcomes.

OBJECTIVE: The purpose of this study is to investigate the outcomes of conventional transarterial chemoembolization (TACE) treatment of hepatocellular carcinoma (HCC) in contemporary clinical practice. MATERIALS AND METHODS: In this single-institution retrospective study, 188 patients underwent conventional TACE for HCC between 2007 and 2013. Medical record and imaging review was used to collect baseline demographic and disease data, tumor response, time to progression (TTP), and progression-free survival (PFS) outcomes, as well as transplant-free survival, calculated from the time of the first conventional TACE treatment. Data were censored in April 2014. RESULTS: The study cohort included 140 men and 48 women (mean age, 60 years; Barcelona Clinic Liver Cancer [BCLC] stage 0 = 5%, BCLC stage A = 41%, BCLC stage B = 28%, BCLC stage C = 15%, and BCLC stage D = 11%) with 207 index tumors (mean size, 4.0 cm; 11% with portal vein invasion) treated with a mean of 1.6 selective (79%) or lobar (21%) conventional TACE sessions. Concurrent thermal ablation was performed for 19% of patients. Objective response rates included size response in 29% (World Health Organization) and 28% (Response Evaluation Criteria for Solid Tumors [RECIST]) of patients, and necrosis response in 79% (European Association for the Study of the Liver) and 70% (modified RECIST) of patients. Median local TTP, distant site TTP, local PFS, and other site PFS were 51.7, 11.2, 10.8, and 10.5 months. Eighteen percent of patients underwent liver transplantation; 48% of United Network for Organ Sharing stage T3 tumors were downstaged to stage T2. Transplant-free survival for the entire cohort was 16.8 months (not reached, 33.9, 16.0, 4.4, and 6.9 months for BCLC stages 0, A, B, C, and D, respectively). Postembolization syndrome requiring extended hospital stay or readmission occurred in only 6% of patients. CONCLUSION: Conventional TACE is effective and safe for HCC therapy and may confer a survival benefit. The current data are in line with reported conventional TACE outcomes, and the minor postembolization syndrome incidence supports the low morbidity of this approach.

Regression of Hepatocellular Carcinoma Lung Metastases after Guyabano Fruit Extract Consumption.

Hepatocellular carcinoma (HCC) is a leading cause of worldwide cancer-related mortality, and even with established treatment paradigms, its global burden demands greater research into therapeutic options. In the following case report, a patient suffering from HCC with lung metastasis demonstrated regression of metastatic disease while consuming guyabano fruit extract in the absence of conventional chemotherapy. While the antineoplastic effects of the guyabano fruit is well documented, there is sparse clinical documentation of HCC regression associated with it, and a better understanding of guyabano and its antineoplastic activity may trigger discovery of novel therapeutic options for this deadly disease.

Pharmacokinetic study of conventional sorafenib chemoembolization in a rabbit VX2 liver tumor model.

PURPOSE: Use of oral sorafenib, an antiangiogenic chemotherapeutic agent for hepatocellular carcinoma (HCC), is limited by an unfavorable side effect profile. Transarterial chemoembolization (TACE) employs targeted intravascular drug administration, and has potential as a novel sorafenib delivery method to increase tumoral concentrations and reduce systemic levels. This study aimed to discern the pharmacokinetics of sorafenib TACE in a rabbit VX2 liver tumor model. METHODS: A 3 mg/kg dose of sorafenib ethiodized oil emulsion was delivered via an arterial catheter to VX2 liver tumors in seven New Zealand white rabbits. Following TACE, serum sorafenib levels were measured at days 0, 1, 2, 3, 7, 10, and 14 until the time of sacrifice, after which rabbit livers were harvested for analysis of sorafenib concentrations within treated tumors and normal liver. Liquid chromatography tandem mass spectrometry was used for drug quantification. RESULTS: Sorafenib uptake within liver tumor and nontumorous liver tissue peaked at mean 3.53 and 0.75 µg/mL, respectively, immediately post-procedure (5:1 tumor to normal tissue drug uptake ratio), before decreasing with a 10-18 hour half-life. Serum sorafenib levels peaked immediately after TACE at a mean value of 58.58 µg/mL before normalizing with a 5.2-hour half-life, suggesting early drug washout from liver into the systemic circulation. Hepatic lab parameters showed transient increase 24 hours post-TACE with subsequent resolution. CONCLUSION: While targeted transarterial delivery of sorafenib ethiodized oil emulsion shows preferential tumor uptake compared to normal liver, systemic washout occurs with a short half-life, resulting in high circulating drug levels.

Transarterial sorafenib chemoembolization: preliminary study of technical feasibility in a rabbit model.

PURPOSE: To test the feasibility of targeted intraarterial administration of the tyrosine kinase inhibitor chemotherapeutic agent sorafenib to inhibit embolotherapy-induced tumor angiogenesis and reduce systemic drug side effects. MATERIALS AND METHODS: The left hepatic lobes of five New Zealand White rabbits (mean weight, 2.7 kg±0.2) were treated with chemoembolization with sorafenib and ethiodized oil emulsion, followed by immediate euthanasia. Postprocedure noncontrast computed tomography (CT) was used to evaluate intrahepatic chemotherapy mixture distribution. Liquid chromatography/tandem mass spectrometry (LC-MS/MS) was then used to directly measure sorafenib concentration in the treated liver tissue. Histopathologic assessment of treated left lobes was performed to identify any immediate toxic effects of the sorafenib solution. RESULTS: Lobar sorafenib chemoembolization was successfully performed in all cases via the left hepatic artery. Sorafenib and ethiodized oil (mean, 6.4 mg±3.8 and 0.95 mL±0.7, respectively) were injected, and CT confirmed targeted left hepatic lobe sorafenib emulsion delivery in all cases. Corresponding LC-MS/MS analysis yielded a mean sorafenib concentration of 94.2 µg/mL±48.3 in treated left lobe samples (n = 5), significantly greater than typical therapeutic drug levels (2-10 µg/mL) achieved with oral sorafenib systemic therapy. Histopathologic assessment showed only mild or moderate nonspecific ballooning degeneration in zone 3 hepatocytes, without tissue necrosis. CONCLUSIONS: Targeted transarterial sorafenib delivery is feasible and results in higher tissue drug levels than reported for systemic sorafenib therapy, without immediate histopathologic tissue toxicity. Future studies should aim to determine the utility of sorafenib chemoembolization in reducing hypoxia-induced vasculogenesis in liver tumors.

Locoregional chemoembolic delivery: prediction with transcatheter intraarterial perfusion MRI.

OBJECTIVE: To our knowledge there is currently no quantitative preprocedural method for predicting the distribution and selectivity of delivery of chemoembolic material during trans-arterial chemoembolization. Transcatheter intraarterial perfusion MRI has been developed as a method of quantifying hepatic arterial perfusion. The purpose of this study was to investigate whether findings at transcatheter intraarterial perfusion MRI before chemoembolization can be used to predict uptake of the chemoembolic material delivered during chemoembolization. SUBJECTS AND METHODS: We compared quantitative prechemoembolization transcatheter intraarterial perfusion MRI parameters with analogous postchemoembolization CT chemoembolic distribution parameters and analyzed correlation using the Pearson correlation coefficient. These MRI and CT parameters included volume of distribution (a metric for volumetric liver perfusion or therapeutic agent delivery) and chemoembolic delivery selectivity factor (a ratio of volume-normalized tumor to background signal intensity that indicates the selectivity of chemoembolic delivery). RESULTS: Twenty-four hepatocellular carcinomas were targeted in 18 patients (14 men, four women; mean age, 66 years), and segmental or lobar chemoembolization with intraprocedural transcatheter intraarterial perfusion MRI was successful in all 18. Transcatheter intraarterial perfusion MRI and CT volume of distribution did not differ significantly (MRI, 233 cm(3); CT, 235 cm(3); p = 0.857). Transcatheter intraarterial perfusion MRI selectivity factor was an underestimate of CT selectivity factor (MRI, 0.20; CT, 0.25; p = 0.005). Prechemoembolization transcatheter intraarterial perfusion MRI and postchemoembolization CT volume of distribution (r = 0.93; p < 0.001) and selectivity factor (r = 0.95; p < 0.001) showed significant correlation. CONCLUSION: Tumor perfusion measured with transcatheter intraarterial perfusion MRI is predictive of uptake of chemoembolic material before delivery. This MRI technique may have utility as a method of quantifying delivery of the therapeutic agent during chemoembolization and, potentially, other liver-directed locoregional therapies.

Confirmation of drug delivery after liver chemoembolization: direct tissue doxorubicin measurement by UHPLC-MS-MS.

Because liver cancer is rarely suitable for surgery, transcatheter arterial chemoembolization (TACE) is used for palliative therapy. In this procedure, an emulsion of doxorubicin in iodized oil is injected directly into liver tumors through a catheter positioned within the artery supplying blood flow to the tumor. At present, there is limited understanding of factors affecting the delivery and dispersion of doxorubicin within treated tumors during TACE. This study addresses the development and application of an ultrahigh-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS-MS) method for rapid confirmation of drug delivery after TACE in a rabbit VX2 liver cancer model. Doxorubicin levels in liver tumors were measured using UHPLC-MS-MS and compared with computed tomography measured levels of iodized oil, a metric used clinically to indicate drug delivery. We found that tissue drug levels determined using UHPLC-MS-MS did not correlate with the regional iodized oil concentration (vehicle) within tumors following TACE, suggesting that chemotherapeutic drugs like doxorubicin spread throughout tumors, and that lack of iodized oil staining in portions of a tumor does not necessarily indicate inadequate therapy during TACE.

Ethiodized oil uptake does not predict doxorubicin drug delivery after chemoembolization in VX2 liver tumors.

PURPOSE: To investigate the accuracy of ethiodized oil as an imaging marker of chemotherapy drug delivery after liver tumor chemoembolization in an animal model of hepatocellular carcinoma. MATERIALS AND METHODS: Eleven VX2 liver tumors (mean diameter, 1.9 cm ± 0.4) in six New Zealand White rabbits were treated with chemoembolization using ethiodized oil and doxorubicin emulsion, followed by immediate euthanasia. Postprocedure noncontrast computed tomography (CT) was used to evaluate intratumoral ethiodized oil distribution and calculate iodine content within four peripheral tumor quadrants and the tumor core at a central tumor slice (N = 55 total tumor sections). Liquid chromatography/tandem mass spectrometry (LC-MS/MS) was then used to directly measure doxorubicin concentration in the same tissue sections. Statistical correlation was performed between tissue iodine content and doxorubicin concentration by using linear regression. RESULTS: Chemoembolization was successfully performed in all tumors via the left or proper hepatic artery. A mean of 0.9 mL ± 0.6 ethiodized oil and 1.8 mg ± 1.2 doxorubicin were injected. CT-calculated tissue iodine content averaged 335 mg/mL ± 218. Corresponding LC-MS/MS analysis yielded a mean doxorubicin concentration of 15.8 µg/mL ± 14.3 in each sample. Although iodine content (391 mg/mL vs 112 mg/mL; P = .000) and doxorubicin concentration (18.0 µg/mL vs 7.2 µg/mL; P = .023) were significantly greater along peripheral tumor sections compared with the tumor core, no significant predictable correlation was evident between these measures (R(2) = 0.0099). CONCLUSIONS: Tissue ethiodized oil content is a poor quantitative predictor of local doxorubicin concentration after liver tumor chemoembolization. Future studies should aim to identify a better imaging marker for chemoembolization drug delivery.