Novel use of peak optimized particle therapy for the delivery of three-dimensional spatially fractionated radiotherapy.

Spatially fractionated radiotherapy (SFRT) has been delivered safely and effectively mostly utilizing beamlets of megavoltage photons in recent years. Particle therapy offers the promise of improved dose distributions with less exposure of surrounding normal tissues. However, most efforts have focused on mimicking the beamlets of traditional SFRT two-dimensional therapy (also known as GRID), potentially sacrificing advantages that could be achieved with scanned particle beams. We, herein, lay out the rationale for and execution of a novel pencil beam scanning proton therapy technique for SFRT that prioritizes pristine Bragg peak delivery in an interleaved and rotated three-dimensional SFRT (LATTICE) format. We propose that this patented (US11478665B2) technique optimizes particle SFRT therapy radiobiologic effect, minimizes normal tissue and superficial dose, and allows for alternative SFRT applications across a course of therapy. This technique lends itself to further exploration in delivery techniques, fractionation, and ultra-high dose rates.