Purpose: The combination of embolic beads with a multi-targeted tyrosine kinase inhibitor that inhibits tumor vessel growth is suggested as an alternative and improvement to the current standard doxorubicin-eluting beads for use in transarterial chemoembolization. This study demonstrates the in vitro loading and release kinetics of sunitinib using commercially available embolization microspheres, and evaluates the in vitro biological efficacy on cell cultures and the resulting in vivo pharmacokinetic profiles in an animal model. Materials and Methods:DC Bead microspheres, 70-150 µm and 100-300 µm (Biocompatibles Ltd., Farnham, United Kingdom), were loaded by immersion in sunitinib solution. Drug release was measured in saline in a USP-approved flow-through apparatus and quantified by spectrophotometry. Activity after release was confirmed in cell culture. For pharmacokinetics and in vivo toxicity evaluation, New-Zealand white rabbits received sunitinib either by intra-arterial injection of 100-300 µm sized beads or per os. Drug concentrations in the plasma and liver tissue were assessed by liquid chromatography-tandem mass spectrometry.Results: Sunitinib loading on beads was close to complete and homogeneous. A total release of 80% in saline was measured, with similar fast release profiles for both sphere sizes. After embolization, drug plasma levels remained below the therapeutic threshold (< 50 ng/ml), but high concentrations at 6 h (14.9 µg/g) and 24 h (3.4 µg/g) were found in the liver tissue.Conclusions: DC Bead microspheres of two sizes were efficiently loaded with sunitinib and displayed a fast and almost complete release in saline. High liver drug concentrations and low systemic levels indicated the potential of sunitinib-eluting beads for use in embolization.

Embolic microspheres or beads used in transarterial chemoembolization are an established treatment method for hepatocellular carcinoma patients. The occlusion of the tumor-feeding vessels by intra-arterial injection of the beads results in tumor necrosis and shrinkage. In this short review, we describe the utility of using these beads as devices for local drug delivery. We review the latest advances in the development of non-biodegradable and biodegradable drug-eluting beads for transarterial chemoembolization. Their capability to load different drugs, such as chemotherapeutics and anti-angiogenic compounds with different physicochemical properties, like charge and hydrophilicity/hydrophobicity, are discussed. We specifically address controlled and sustained drug release from the microspheres, and the resulting in vivo pharmacokinetics in the plasma vs. drug distribution in the targeted tissue.

Purpose To measure plasmatic sunitinib concentration (PSC) and intratumoral sunitinib concentration (ITSC) after transcatheter arterial chemoembolization (TACE) with two different sizes of sunitinib-eluting beads (SEBs) in rabbits with VX2 hepatic allografts and to investigate treatment effects on vascular endothelial growth factor receptor type 2 (VEGFR2) phosphorylation, tumor volume, and histopathologic changes. Materials and Methods The protocol was approved by the French Ethics Committee for Animal Experiments (Comité d'Ethique en Expérimentation Animale du Centre INRA de Jouy-en-Josas et AgroParisTech, or COMETHEA, approval no. 11/028). Two experiments were performed. In the first, seven animals received 0.05 mL of 100-300-μm SEBs (1.5 mg of sunitinib) in the hepatic artery, and six animals received saline injections. In the second, eight animals received 0.05 mL of 70-150-μm SEBs (1.5 mg of sunitinib), seven received 0.05 mL of 70-150-μm unloaded beads, and seven received oral sunitinib (6 mg every day). Tumor size was monitored with ultrasonography. PSC, ITSC, and phosphorylation of VEGFR2 were assessed on days 1 and 14. After the animals were sacrificed, histopathologic analysis was performed. The Kruskal-Wallis test, Mann-Whitney U test, and Fisher exact test were used to look for statistically significant differences between groups. Results Maximum PSC after TACE with 100-300-μm SEBs was 0.002 μg/mL on day 1. ITSC was 17.8 μg/g on day 1 and 0.16 μg/g on day 14. After TACE with 70-150-μm SEBs, ITSC was 40.4 μg/g on day 1 and 27.4 μg/g on day 14. Phosphorylation of VEGFR2 was inhibited until day 14 after TACE with both sizes of SEBs. The size of VX2 tumors treated with 70-150-μm SEB TACE increased less (-2%) than that of tumors treated with unloaded beads (+42%) and oral sunitinib (6 mg every day; +1853%; P = .044). Conclusion SEB TACE resulted in minimal PSC, high ITSC, and sustained VEGFR2 phosphorylation inhibition until day 14. (©) RSNA, 2016.

UC-associated carcinomas presented aneuploidy at significantly higher frequency than sporadic colorectal carcinomas (P < 0.0006). UCCs and aneuploid SCCs share a similar prognosis inferior to that of diploid SCCs. Aneuploidy proved to be the strongest independent prognostic marker for R0-resected colorectal cancer patients overall.