Abstract
<title>Abstract</title> <p> <bold>Background</bold> : Tumor treating fields (TTF) therapy is an established treatment for human glioblastoma, but its physical viability, current requirements, and optimal array configurations have not been evaluated in canines. Hypothesis/Objectives: To evaluate the physical feasibility and therapeutic volume coverage of TTF delivery in a canine glioma model, and to optimize transcutaneous and epicranial electrode configurations. Animals: In silico model derived from imaging data of one 5-year-old neutered male French Bulldog with spontaneous glioma. <bold/> <bold>Materials and methods:</bold> A three-dimensional finite element head model was constructed from co-registered MRI and CT data. Comprehensive sets of electrodes were defined on both the scalp and skull surfaces. Electric field distributions and therapeutic enhancement ratio (TER) values were calculated for 71,415 configurations of one or two pairs of perpendicular electrodes across a range of current amplitudes. An optimization paradigm was used to identify the best configurations for maximizing the percentage of tumor volume achieving complete growth arrest. <bold>Results</bold> : Complete tumor growth arrest (100% volume coverage at TER > 1) was achieved with transcutaneous TTF at 530 mA for one-pair TTF and 500 mA for two-pair TTF, while epicranial placement required only 125 mA in both cases. Optimized two-pair configurations yielded near-perpendicular field directions within the tumor while maintaining overall coverage equivalent to one-pair TTF. Given clinical efficacy of human TTF with higher currents and lower fields, canine TTF is expected to be safe and feasible. <bold>Conclusions and clinical importance:</bold> In this anatomically realistic model of a dog with glioma, transcutaneous and epicranial electrodes generated intratumoral fields that met TER-derived coverage thresholds at the investigated current amplitudes. These findings support further in vitro, ex vivo, and in vivo evaluation of canine-specific TTF frequency, biological response, and thermal safety, as well as assessment of electrode fixation and treatment tolerability. In vitro studies in particular may help clarify cellular and tumor-specific responses to the applied field parameters before advancing to more complex biological models. Epicranial placement requires separate surgical feasibility and safety assessment. </p>