Goals: To examine the safety and effectiveness of percutaneous radio-frequency ablation therapy (PRAT) for malignant liver tumors, using a needle with cluster radio-frequency (RF) electrodes.
Study: The subjects were 13 patients with solitary malignant liver tumors: 10 had hepatocellular carcinoma and 3 had metastatic liver tumors. One session of PRAT with cluster RF electrodes was performed until roll-off occurred two times. Dynamic computed tomography (CT) and fine needle tumor biopsy under ultrasonographic guidance were conducted to assess the therapeutic efficacy. Aspartate aminotransferase, alanine aminotransferase, lactic dehydrogenase, and total bilirubin were evaluated before and 1, 3, and 7 days after PRAT.
Results: There were no serious complications. Aspartate aminotransferase, alanine aminotransferase, and lactic dehydrogenase levels peaked 1 day after PRAT and decreased thereafter. No icterus occurred. Of the 13 tumors, 12 showed complete necrosis on dynamic CT; however, one of them showed histologically incomplete necrosis in the tumor biopsy. In both of the ineffective cases, the tumors were located near relatively large vessels. There was no recurrence in the liver in all cases of PRAT that were effective (observation periods: 6--14 months; mean, 10 months).
Conclusions: Percutaneous radio-frequency ablation therapy using a clustered electrode is a safe and effective treatment of malignant liver tumors, if the tumor is not located near the large vessels.