1814 - General Methodology to Optimize Tumor Treating Fields Delivery Utilizing Numerical Simulations

Background

Tumor Treating Fields (TTFields) are intermediate frequency, alternating electric fields that non-invasively treat cancer. Transducer arrays positioned on the skin in proximity to the targeted tumor transmit TTFields. A post-hoc analysis [Ballo et al. Red Jour. 2019 In Press] has shown that increased patient usage (percent of time on active treatment) and intensity of TTFields delivery direct to the tumor improved survival. Optimal array positioning may enhance TTFields intensity at the tumor site to improve patient experience and survival. Minimization of array exposure area would enhance patient comfort levels and usage to improve survival. Optimizing TTFields delivery and distribution depends on array positioning and geometry, patient anatomy, and the heterogeneous electrical properties of different tissues. We present methodology to optimize TTFields delivery using numerical simulations.

Methods

TTFields delivery to the brain, lung, and abdomen utilizing representative computational models was investigated. The effects of transducer array size and position on field distribution within the phantoms was analyzed, and an approach to optimize TTFields delivery was developed.

Results

Field intensity was typically the greatest in between arrays, with larger arrays transmitting higher field power. Anatomical features, such as bones (spine) or a resection cavity significantly influenced field intensity within this region. A generalized methodology to optimize TTFields delivery for improved patient care was based on: (1) Striking a balance between maximal field intensity (largest arrays feasible) and minimal skin exposure to arrays in the disease area; (2) Positioning virtual arrays on a representative, computational patient model to test tumor localization between arrays, to simulate TTFields delivery to patient, and to assess optimal delivery; and (3) Applying an iterative algorithm to shift arrays around their initial positions until field intensity is maximized directly to the tumor bed.

Conclusions

A generalized treatment methodology as presented by these data will optimize TTFields delivery to the tumor site. Effective TTFields treatment planning is expected to improve patient outcomes.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Novocure.

Funding

Novocure.

Disclosure

N. Urman: Full / Part-time employment: Novocure; Shareholder / Stockholder / Stock options: Novocure. Z. Bomzon: Full / Part-time employment: Novocure; Shareholder / Stockholder / Stock options: Novocure. H.S. Hershkovich: Full / Part-time employment: Novocure; Shareholder / Stockholder / Stock options: Novocure. E.D. Kirson: Full / Part-time employment: Novocure; Shareholder / Stockholder / Stock options: Novocure. A. Naveh: Full / Part-time employment: Novocure; Shareholder / Stockholder / Stock options: Novocure. R. Shamir: Full / Part-time employment: Novocure; Shareholder / Stockholder / Stock options: Novocure. E. Fedorov: Full / Part-time employment: Novocure; Shareholder / Stockholder / Stock options: Novocure. C. Wenger: Full / Part-time employment: Novocure; Shareholder / Stockholder / Stock options: Novocure. U. Weinberg: Full / Part-time employment: Novocure; Shareholder / Stockholder / Stock options: Novocure.