The primary endpoint was the time to recurrence(TTR) was measured from the date of treatment to the time when the recurrent tumor was first diagnosed. At spiral CT after treatment, residual viable tumor tissue was considered to be present if enhancing areas were seen within the tumor on either arterial phase or portal venous phase images. Depending on the initial random treatment assignment, RFA-125I or RFA alone was repeated. Magnetic resonance (MR) imaging was performed if there was uncertainty at CT as to whether residual viable tumor tissue was present.