A new treatment method to intercept collaterals with silicone rubber sheeting, called "wrapping therapy", was used for 18 patients with advanced hepatocellular carcinomas having collateral feeders from other organs surrounding the liver. Chemoembolization in 17 of the 18 patients in whom it had been conducted more than once, had proven ineffective. Obvious collateral feeders (parasitic branches) to the tumors were recognized on hepatic angiograms in two-thirds of the patients. This procedure was followed by regional chemotherapy and/or chemoembolization. The 3- and 4-year survival rates of the patients after "wrapping therapy" were 54% and 54%, respectively. This therapy is worth using for hepatocellular carcinomas uncontrolled by arterial therapy because of development of collateral feeders.