An investigation was carried out into the effects of lipiodol-transcatheter arterial chemoembolization (L-TACE) therapy on hepatocellular carcinoma (HCC) and metastatic liver cancer, as well as the effects of oral 5-fluorouracil administration after L-TACE. For L-TACE, lipiodol mixed with adriamycin (doxorubicin) was injected through a catheter inserted into the tumor feeding artery and this was followed by embolization with a gelatin sponge. Twenty national hospitals throughout Japan participated in this multicenter co-operative open trial. A total of 102 patients became the subjects of study, including 75 HCC patients, 12 metastatic liver cancer patients treated with L-TACE, and 15 HCC patients who had hepatectomy after L-TACE. In 22% of the HCC patients and in 42% of the metastatic liver cancer patients, the tumor size was reduced by more than 50% after L-TACE. 73% of the 63 HCC patients showed a more than 50% reduction of the levels of serum alpha-fetoprotein. Although the survival rates of the HCC patients who had a hepatic resection were better than those who had not, there was no statistically significant difference between the survival rates of the HCC patients and those of the metastatic liver cancer patients treated with L-TACE. The survival rates of the HCC patients after L-TACE did not change as a result of oral 5-fluorouracil administration. It was therefore concluded that L-TACE is an effective way of treating both HCC patients and metastatic liver cancer patients, and that repeated L-TACE should be considered for some patients whose serum levels of alpha-fetoprotein rose again after L-TACE. Further follow-up studies will be needed to discover the effects of oral chemotherapy after L-TACE.