Optimal dose-response relationship in electrolytic ablation of tumors with a one-probe-two-electrode device

Abstract

Electrolytic ablation (EA), a medical treatment used in solid tumor ablation due to its minimum side effects and low cost, consists in the passage of a low constant electric current through two or more electrodes inserted in the tissue thus inducing pH fronts that produce tumor necrosis. Combined with a recently introduced one-probe two electrode device (OPTED) this procedure results in a minimally invasive treatment. Despite its success, EA has drawbacks such as the difficulties in determining the optimum dose-response relationship between the applied current, treatment time and necrotized tumor volume (NTV) and choosing a reliable dose parameter. In this work, a theoretical model is introduced describing the EA/OPTED as an electrolytic process and the underlying electrochemical reactions through the Nernst-Planck equations for ion transport. Model results show that the coulomb dosage is a reliable dose parameter and predicts an optimal dose-response relationship for a given tumor size subjected to an EA/OPTED, considering the optimum as the minimum coulomb dosage necessary to achieve total tumor destruction while minimizing healthy tissue damage. Moreover, it predicts a nonlinear relationship between coulomb dosage and NTV, dosage and NTV scaling as Q1.4. Consequently, these results could have a significant impact on dose planning methodology aimed at improving the effectiveness of the electrolytic ablation.