Effects of Arsenic Trioxide on Radiofrequency Ablation of VX2 Liver Tumor: Intraarterial versus Intravenous Administration

Objective: Arsenic trioxide ($As_{2}O_{3}$) can be used as a possible pharmaceutical alternative that augments radiofrequency (RF) ablation by reducing tumor blood flow. The aim of this study was to assess the effect of intraarterial and intravenous administration of $As_{2}O_{3}$ on RF-induced ablation in an experimentally induced liver tumor. Materials and Methods: VX2 carcinoma was grown in the livers of 30 rabbits. $As_{2}O_{3}$ (1 mg/kg) was administered through the hepatic artery (n = 10, group A) or ear vein (n = 10, group B), 30 minutes before RF ablation (125 mA ${\pm}$ 35; 90 ${\pm}$ $5^{\circ}C$). As a control group, 10 rabbits were treated with RF ablation alone (group C). RF was intentionally applied to the peripheral margin of the tumor so that ablation can cover the tumor and adjacent hepatic parenchyma. Ablation areas of the tumor and adjacent parenchymal changes among three groups were compared by the Kruskal-Wallis and Mann-Whitney U test. Results: The overall ablation areas were 156 ${\pm}$ 28.9 $mm^{2}$ (group A), 119 ${\pm}$ 31.7 (group B), and 92 ${\pm}$ 17.4 (group C, p < 0.04). The ablation area of the tumor was significantly larger in group A (73 ${\pm}$ 19.7 $mm^{2}$) than both group B (50 ${\pm}$ 19.4, p = 0.02) and group C (28 ${\pm}$ 2.2, p < 0.01). The ratios of the tumoral ablation area to the overall ablation area were larger in group A (47 ${\pm}$ 10.5%) than that of the other groups (42 ${\pm}$ 7.3% in group B and 32 ${\pm}$ 5.6% in group C) (p < 0.03). Conclusion: Radiofrequency-induced ablation area can be increased with intraarterial or intravenous administration of $As_{2}O_{3}$. The intraarterial administration of $As_{2}O_{3}$ seems to be helpful for the selective ablation of the tumor.