Percutaneous ablation is a commonly used modality of treatment when resection is not possible for HCC. Other local modalities are radiofrequency ablation or chemo embolization. When direst intratumor injection is used, alcohol is most commonly used and it is FDA approved for this purpose. However, acetic acid is more potent in animal models. Only a few studies tested the various modlaities against one another.
A systematic review of RCTs published from 1978 to 2002 identified seven RCTs including a total of 516 patients comparing embolization vs. conservative management, five of which assessing chemoembolization with doxorubicin or cisplatin. Survival benefits were obtained in two studies, one of which identifies treatment response as an independent predictor of survival. Meta-analysis showed a beneficial survival effect of embolization/chemoembolization in comparison with the control group. Overall, this effect may be considered modest, as is expected to occur in advanced neoplasms. Survival benefits were not identified with embolization alone, but the number of individuals analyzed is still low. There is no good evidence for the best chemotherapeutical agent and the optimal re-treatment strategy.
Three small RCT assessing either chemoembolization in combination with percutaneous ablation or lipiodolization have been published in this period A German study reported no survival differences between a combination of chemoembolization and PEI vs. chemoembolization alone in 58 patients. Therapy using reservoir intra-arterial infusion has been employed in patients with advanced HCC with disappointing results. A low-quality study assessing lipiodolization with carboplatin (150 mg/m2) compared with doxorubicin (20 mg/m2) in 65 Chinese patients, showed significant survival benefits favoring the carboplatin arm (16.9 vs. 12.1 months, P = 0.0257). Further studies are required to confirm these data.
In summary, there is no conclusive evidence to consider intrahepatic injection to be better or even equivalent to emblolization; however, alcohol ablation is widely used in the USA. Acetic acid is less frequently used and there are no comparative studies of it versus alcohol. NCCN speaks of “ablation” and thus avoids the issue of the agent (alcohol versus acetic acid);however, it considers “ablation” standard of care.
Brunken C, Topp S, Tesch C, et.al. System Effects and Side Effects of Interstitial Techniques Used in Liver Tissue. American College of Surgeons 1999; 188, No.6: 636-642.
Usha Dutta (2000) Treatment of hepatocellular carcinoma Journal of Gastroenterology and Hepatology 15 (8), 822–824.
Llovet JM, Bruix J. Systematic review of randomized trials for unresectable hepatocellular carcinoma: chemoembolization improves survival. Hepatology 2003; 37: 429–42.
Akamatsu M, Yoshida H, Obi S, et al. Evaluation of transcatheter arterial embolization prior to percutaneous tumor ablation in patients with hepatocellular carcinoma: a randomized controlled trial. Liver Int 2004; 24: 625–9.
Becker G, Soezgen T, Olschewski M, et al. Combined TACE and PEI for palliative treatment of unresectable hepatocellular carcinoma. World J Gastroenterol 2005; 11: 6104–9.