Biodistribution of 10B in a rat liver tumor model following intra-arterial administration of sodium borocaptate (BSH)/degradable starch microspheres (DSM) emulsion

Abstract

We reported that intra-arterial administration of borocaptate sodium (BSH)/lipiodol emulsion provided selectively high 10B concentrations (approximately 200 ppm 6 h after administration) in experimental liver tumors. In the present study, we investigated the pharmacokinetics of BSH following intra-arterial administration of BSH with other embolizing agent, degradable starch microspheres (DSM). The 10B concentration in the tumor at 1 h after administration of BSH with DSM was 231 ppm. At 6 h, the 10B concentration in the tumor in BSH with DSM group was 81.5 ppm. The 10B concentration in the liver at 1 h after administration of BSH with DSM was 184 ppm. At 6 h, the 10B concentration in the liver in BSH with DSM group was 78 ppm. The tumor/liver 10B concentration ratios (T/L ratio) in the “BSH+DSM” group were significantly smaller than those in the “BSH+lipiodol” group at 1 h (1.4 vs. 3.6) and 6 h (1.1 vs. 14.9). BSH/DSM-boron neutron capture therapy (BNCT) was not suitable for treatment of multiple liver tumors due to the low T/L 10B concentration ratio. However, the high 10B accumulation in the liver tumors following intra-arterial administration of BSH/DSM emulsion suggests that BSH/DSM-BNCT has the potential for application to malignant tumors in other sites.