Transarterial chemoembolization for unresectable hepatocellular carcinoma: Meta-analysis of randomized controlled trials

PURPOSE: To review the available evidence of chemoembolization for unresectable hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Computerized bibliographic searches with MEDLINE and CANCERLIT databases from 1980 through 2000 were supplemented with manual searches, with the keywords "hepatocellular carcinoma," "liver cell carcinoma," "randomized controlled trial [RCT]," and "chemoembolization." Studies were included if patients with unresectable HCC were enrolled and if they were RCTs in which chemoembolization was compared with nonactive treatment (five RCTs) or if different transarterial modalities of therapy (13 RCTs) were compared. Data were extracted from each RCT according to the intention-to-treat method. Five of the RCTs with a nonactive treatment arm were combined by using the random-effects model, whereas all 18 RCTs were pooled from meta-regression analysis. RESULTS: Chemoembolization significantly reduced the overall 2-year mortality rate (odds ratio, 0.54; 95\% CI: 0.33, 0.89; P =.015) compared with nonactive treatment. Analysis of comparative RCTs helped to predict that overall mortality was significantly lower in patients treated with transarterial embolization (TAE) than in those treated with transarterial chemotherapy (odds ratio, 0.72; 95\% CI: 0.53, 0.98; P =.039) and that there is no evidence that transarterial chemoembolization is more effective than TAE (odds ratio, 1.007; 95\% CI: 0.79, 1.27; P =.95), which suggests that the addition of an anticancer drug did not improve the therapeutic benefit. CONCLUSION: In patients with unresectable HCC, chemoembolization significantly improved the overall 2-year survival compared with nonactive treatment, but the magnitude of the benefit is relatively small.