Twenty-six cases of hepatocellular carcinoma were divided randomly into 3 groups, treated by transcatheter hepatic arterial chemo-embolizations with agents of MMC 20 mg, MMC 20 mg plus lipiodol 10 ml, and MMC 20 mg plus MTXmc 150 mg, respectively, 2 to 3 weeks before surgery. Pathologically, all main tumors in the resected specimens were necrosed to a certain extent, with extensive necrosis in the MMC-MTXmc group, whereas there was no necrosis of cancer cells in tumor capsules, daughter nodules, and intraportal vein emboli. We consider that the transcatheter arterial chemoembolization is effective in reducing tumor burden, but not enough in eradicating all cancer cells, so surgical resection should be carried out whenever resection is possible. For preventing tumor recurrence, direct puncture of the main trunk of the portal vein to infuse 500 mg of 5-FU during operation and injection of MMC 20 mg through a catheter inserted into the hepatic artery 4 weeks after operation is suggested.