Purpose
We have investigated the annual frequency of recurrent intrahepatic tumors and the doubling time of regrowing tumors after transhepatic arterial chemoembolization (TAE) to know the proper time for subsequent TAE. Materials and Methods: Among cases in which a previous TAE was performed, 28 cases showed definite intrahepatic recurrence and 7 cases showed a regrowing tumor in the follow-up liver CT scan and/or hepatic angiography. Resnlts: The annual frequency of intrahepatic recurrence in the 28 tumors was 71.4% (20/28) within one year and 100% within 6 years. The mean doubling time of 7 regrowing tumors was 68.3 days. Conclusion: We concluded that periodically repeated TAE is needed for further treatment of the recurrent and regrowing tumors.