Hepatic arterial chemoembolization with CDDP microcapsules. Experimental studies

After cis-diamminedichloroplatinum ethylcellulose microcapsules (CDDPmc) and unencapsulated CDDP were infused into the hepatic arteries of New Zealand rabbits, both CDDP concentrations in the circulating blood and in hepatic tissue were measured at different time intervals. In the rabbits infused with CDDPmc, the CDDP concentration was maintained at a high level for a significantly longer time in the hepatic tissue and the maximum CDDP level in the circulating blood was greatly reduced, as compared with those in the rabbits infused with unencapsulated CDDP. The tumoricidal effects of arterial infusion of CDDPmc were also evaluated in a model of liver tumor in rats. The therapeutic effects on rat liver tumor of CDDPmc were superior to those of unencapsulated CDDP and blank ethylcellulose microcapsules. The rats treated with CDDPmc showed a significantly lower tumor growth ratio, more extensive tumor necrosis and longer survival time. The results of this study indicate that CDDPmc is a more potential dosage from than conventional CDDP for hepatic arterial infusion in the treatment of liver cancer.