MODL-13. DEVELOPMENT OF TUMOR TREATING FIELDS (TTFIELDS) ARRAYS FOR TREATMENT OF HEAD TUMORS IN MICE MODELS

Abstract

Abstract INTRODUCTION Glioblastoma (GBM) is the most common malignant brain tumor. Tumor Treating Fields (TTFields) therapy is an approved treatment for GBM, delivered continuously by two array pairs placed on the skin surrounding the tumor region. Currently, most GBM animal models are based on mice. Since arrays for TTFields application to the mouse head are lacking, GBM-TTFields in vivo studies are limited. The small dimensions and specific geometries of the mouse head make the development of such arrays challenging. METHODS We tested different array layouts to identify one that will optimally accommodate the geometries of the mouse head while minimally restricting head movement. Additionally, we investigated adhesive tapes for array attachment to the skin, to allow good adherence and hence provide efficient treatment delivery. To validate that the selected array layout delivers therapeutic field intensity to the desired region, we performed simulations and fields measurements. RESULTS To overcome the issue of small head size we developed a layout in which the arrays on the head were divided into two smaller disks, with the opposing arrays situated on the mouse torso. We also identified a thin and transparent adhesive tape that facilitated the correct positioning of the arrays on the mouse head, offered good tackiness, and allowed for easy removal without leaving residual adhesive on the skin. The arrays met the minimum treatment requirements: field intensity ≥ 1 V/cm RMS, current ≥ 50 mA, usage ≥ 75%. CONCLUSIONS Our newly developed mouse head arrays are a flexible construct, that adheres strongly to the skin to enable efficient electric field delivery. By facilitating TTFields delivery to the heads of mice, we will expand the scope of GBM treatment research and will contribute to further advance this field.