Electrodes of radiofrequency ablation for malignant lung tumors: a narrative review of advances, applications, and prospects.

Background and Objective: Radiofrequency ablation (RFA) is one of the most widely adopted thermal ablation modalities for patients with inoperable malignant lung tumors, including primary lung cancer and pulmonary metastases. Compared with other ablation techniques such as microwave and cryoablation, RFA has a longer clinical accumulation and technical evolution, and its therapeutic effect relies primarily on the delivery of thermal energy within tissues, placing higher demands on thermal field distribution. As the core energy-conducting component of RFA system, the radiofrequency (RF) electrode significantly affects the morphology and extent of the ablation zone. Notably, owing to the lungs' unique anatomical architecture, precise deployment of such devices is crucial to ensure effective ablation and minimize potential complications. This study focuses on the application and challenges of RF electrodes in pulmonary ablation and highlights the prospective development of RF electrode technology. Methods: This study conducted a review by searching through databases including PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Google Scholar. Studies focusing on the structure, design, or ablation performance of RF electrodes in malignant lung tumors were selected. Based on these findings, a narrative review was generated. Key Content and Findings: RF electrodes available for pulmonary ablation can be mainly classified into monopolar, bipolar, and multipolar electrodes. And the optimized electrode designs-such as cooling, expandable, or bipolar configurations-can better adapt to tumors of different morphologies and sizes by improving the tissue-electrode coupling and energy deposition, enabling larger, more controllable ablation zone than conventional designs. In the future, RF electrode technology will be further integrated with structural and functional optimization, combination therapy strategies (such as targeted drug delivery), and precise intelligent control system to offer stronger effectiveness and personalized minimally invasive treatment strategies to lung tumor patients. Conclusions: The geometric and conductive characteristics of RF electrodes have been proven to significantly influence the effectiveness and safety of RFA for lung tumors. Future developments should focus on optimizing electrode configuration and refining energy delivery strategies, which are crucial for achieving controllable and uniform ablation zones in lung tumors.