The Experimental and Clinical Studies on Percutaneous Ethanol Injection Therapy (PEIT) for Hepatocellular Carcinoma

Abstract

The antitumor effect of PEIT for HCC was examined experimentally and clinically. Histological examination of normal rat liver after an ethanol injection showed coagulative necrosis and hematoidin deposition suggesting ischemic change at the central injected area and circulatory disturbance around the central injected area. Blood flow and vascular structure of VX2 tumor implanted to rabbit liver were examined before and after an ethanol injection. After the injection, significant decrease of tumor blood flow and disappearance of tumor vessels were observed. Histological examination revealed coagulative necrosis of the tumor and thrombosis in the area adjacent to the tumor. PEIT was performed in 37 patients with HCC. The 11 patients with a single tumor of 2 cm or less in diameter treated by PEIT alone did not showed recurrence, and the 3 year survival rate was 74%. Histological examination of specimens obtained surgically or at autopsy was made after PEIT. Coagulative necrosis of the whole tumor including intracapsular invasion and forma tion of thrombi were observed. Hematoidin was also detected in the necrotic tumor tissue. Ethanol injection caused following changes: 1. Coagulative necrosis of tumor cells at the injected site.2. Arterial and portal venous occulusions at the injected site.3. Circulatory failure due to destruction of vascular structure and thrombus formation leading to parenchymal necrosis at the peripheral portion of an ethanol injection.