Clinical

Multiple-electrode radiofrequency ablation useful for hepatic malignancies

Last Updated: 2007-07-11 14:59:10 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Percutaneous multiple-electrode radiofrequency ablation is a safe and effective treatment for large or multiple hepatic malignancies, according to a report in the June issue of the American Journal of Roentgenology.

"One of the biggest limitations of current radiofrequency ablation techniques is the inability to effectively treat large tumors," lead author Dr. Paul Laeseke, from the University of Wisconsin in Madison, said in a statement. "Current radiofrequency ablation systems can only power one electrode and create relatively small ablation zones," which complicates treatment of large tumors.

Recently, however, a monopolar radiofrequency system incorporating multiple electrodes became available for clinical use. In the present study, the researchers describe their experience using this system, the Cool-tip radiofrequency Switching Controller (Valleylab).

Twenty-three patients with 38 malignant hepatic tumors (2.7 cm mean diameter) underwent 26 radiofrequency ablation sessions using the new system. Under CT and ultrasound guidance, the electrodes were placed in close proximity to treat large tumors or were placed apart to treat several tumors at the same time.

CT evaluation immediately after treatment and at 1, 3, 6, 9, and 12 months was used to assess the effect of ablation.

Local control was achieved in all but one of the tumors. For 34 of the tumors, just one treatment session was needed to achieve control.

Using the multiple electrode approach to ablating large tumors rather than the standard single electrode approach cut the procedure time by 54%, the authors note.

Complications seen in the study group included one death due to pulmonary embolus, one asymptomatic perihepatic hemorrhage, and one pneumothorax.

"While the short-term results are promising and demonstrate that multiple-electrode radiofrequency ablation is safe and effective, longer term follow-up is needed to determine the impact of multiple-electrode radiofrequency ablation on patient survival and tumor recurrence rates," Dr. Laeseke noted.

Am J Roentgenol 2007;188:1485-1494.