Degradable starch microspheres (DSM, Pharmacia) are specially formulated cross-linked starch microspheres about 45 microns in diameter. The microspheres are degraded by serum amylase and become progressively smaller with t1/2 for complete dissolution between 20 and 30 min. in vitro (in normal serum). In vivo, DSM-occluded microcirculation was observed in lobular artery of liver and disappeared 60 minutes after administration; then PAS-positive debris, which was suspected to be degraded DSM, was found in intrahepatic tissues. We also carried out comparative studies on regrowth liver in rats as an index of 3H-thymidine incorporation to determine the influence for surgical operation. DSM + adriamycin (ADM) was injected into intrahepatic artery at 2 and 5 days before partial liver resection. In DSM + ADM group, regrowth of liver tissue was inhibited with injection 2 days before, while injection 5 days before had no influence. Since the usefulness of DSM combined with anticancer agents had been indicated by the experimental results mentioned above, we carried out a clinical study (phage II). Chemoembolization therapy was undertaken in combination with DSM in 6 patients each with primary and metastatic liver cancers. Six cases were evaluated as Partial Response (PR). Recently, we performed clinical trials to investigate the combination with noradrenaline, too. Noradrenaline was suggested to enhance the effect of DSM.