HCC patients with tumors >5 cm in diameter, regardless of involvement in the intrahepatic and extrahepatic portal branches participated in the study. Patients were randomized allocated in liver transplantation (LT) only group and LT plus ADV-TK therapy group. All patients received orthotopic liver transplantation; in the LT plus ADV-TK group, ADV-TK therapy was delivered to patients twice.

Inclusion Criteria:

• 18～70 years of age (Male and Female).
• Clinical diagnosis of advanced hepatocellular carcinoma who could accept liver transplantation
• Patients who had unresectable HCC >5 cm and no metastasis in lungs and bones were eligible to participate in this study. Tumor involvement in the intrahepatic and extrahepatic portal branches was not considered to be an exclusion criterion.
• No prior chemotherapy, radiation therapy, targeted therapy or other kind of biological treatment within 4 weeks.
• Provide written informed consent

Exclusion Criteria:

• Metastasis in lungs and bones
• Invasion in main vescular.
• Contraindications of liver transplantation
• Contraindications of operation of other organ system
• Hypersensitivity to adenovirus, GCV or similar drugs
• Accept clinical trials of other drugs
• Immunological deficit
• Active pregnancy
• Unable or unwilling to sign informed consents