A REVIEW OF TUMOR ABLATION APPLICATORS AND THEIR ROLE IN IRREVERSIBLE ELECTROPORATION THERAPY

Abstract: Electroporation is a phenomenon involving the formation of pores in cell membranes under the influence of short high voltage electric pulses. Depending on the parameters of the pulses, it can be either reversible or irreversible. Reversible electroporation (RE) is widely used in biology and medicine, including in electrochemotherapy (ECT) and gene electrotransfer (GET). In contrast, irreversible electroporation (IRE) is an innovative, non-thermal method of tumor ablation, based on the permanent disruption of cell membranes leading to cell death – primarily through programmed apoptosis rather than necrosis. IRE differs from traditional ablation techniques that rely on energy sources such as radiofrequency, microwaves, laser light, or cryoablation, as it does not utilize thermal effects. This allows for the precise removal of cancerous lesions located near temperature sensitive structures, such as blood vessels, bile ducts, or nerves. A key factor in the effectiveness of IRE therapy is the design and configuration of applicators, which are responsible for delivering electric pulses to the tissue. The aim of this study is to review the current technological solutions used in applicators designed for IRE, with particular emphasis on their construction, types of electrodes, spatial arrangements, material properties, and other operational parameters. The paper presents and compares available types of applicators used both clinically and experimentally, highlighting their impact on the effectiveness of ablation procedures. Special attention is given to understanding the biological and physical foundations of the electroporation phenomenon as the basis of this groundbreaking cancer treatment method.