Hepatocellular carcinoma (HCC) is a common disease in the world and Vietnam. There are many methods of treatment which depends on its stage. Aims: to assess the clinical efficacy of transarterial oily chemoembolization (TOCE) combined with radiofrequency ablation (RFA) for patients with unresectable hepatocellular carcinoma, and compared with that of TOCE alone. Patients and methods: a prospective study conducted 224 patients with HCC 3.1-8.0 cm in largest diameter treated by TOCE plus RFA (121 pts) or TOCE alone (103 pts). End points included overall survival, completed tumor necrosis rate, tumor size shrunk rate, and recurrent after treatment. Results: Mean follow-up period was 20.7 months. Mean survival time was 19.2 + or - 13.9 months in the combined group, longer than that in TOCE alone group (15.1 + or - 10.2, P =0.016). The 1, 2, 3 year survival rates were better in the combined group (100 percent, 90.6 percent, 57.9 percent) compared with in the TOCE alone group (97.4 percent, 82.6 percent, 26.6 percent, p=0.007). The completed tumor necrosis rate after 1 month of treatment in the combined group was 76.6 percent, higher than that in TOCE group (62.9 percent
p=0.019). The tumor shrunk rate after 3 months of treatment in the combined group (70.2 percent) was also higher than that in the TOCE group (51.2 percent
p=0.001). The recurrent rate was lower in the combined group compared with that in the TOCE group (17.4 percent vs 37.8 percent, P 0.001). Conclussions: Chemoembolization combined with RFA provided better clinical efficacy for treatment of unresectable HCC larger than 3cm, compared with chemoembolization alone.