[Experimental studies of transcatheter portal embolization]

The effects of transcatheter portal embolization (TPE) on energy charge (EC) and hepatic blood flow of the rat liver (HBF) were investigated. The antitumor effects on minimal tumor nodules inoculated into the rat liver via the portal vein were evaluated by the alphafetoprotein (AFP) levels and survival period after TPE. The EC of the embolized lobes was significantly decreased after TPE, as compared with the control groups, but was restored 3h later. The HBF of the embolized lobes was reduced 1h after TPE, but was restored in 1 day when TPE was performed by means of temporary embolus. When permanent embolus was used for TPE, decreased HBF persisted for at least seven days. On the other hand, HBF of the non-embolized lobes was not altered in both groups. When TPE was performed after TAE using temporary embolus, the intervals of 14 days were required for normal liver tissue to be preserved. TPE performed 3 days after inoculation of cancer cells into the rat liver caused prolongation of the survival period and decrease in the level of AFP. These results indicate that TPE does not produce marked damage to the liver and has antitumor effects on minimal tumor nodules. TAE followed by TPE may be useful for therapy of unresectable liver tumor.