Creation of large thermal lesions in liver using saline-enhanced RF ablation

Liver cancer, especially metastatic colorectal cancer, is a significant health concern. In the United States, half of the 157,000 new cases of colorectal cancer will develop metastases in the liver, which will lead to over 17,000 deaths. The current standard of practice for treating liver cancer is surgical resection, but only 10% of patients are eligible for this procedure. Thermal ablation using radiofrequency energy is a promising alternative therapy, but it can only treat small tumors. We have developed a system using saline-enhanced radiofrequency ablation for treating large liver tumors. Our system uses the radiofrequency energy to heat tissue with simultaneous injection of warm saline through the electrode to prevent tissue charring and impedance rises (common to radiofrequency ablation) and to convect the thermal energy deeper into the tissue to treat larger volumes than previously possible. Our technique has created thermal lesions in ex vivo liver tissue that are 2.5 times as large as those created by conventional radiofrequency electrodes.