Raster Scanning Helium Ion Beam Therapy Development And Validation Of A Novel Treatment Planning System For Biophysical Modeling And Optimization

Since 2009, over 5000 patients have been treated with proton (1H) and carbon (12C) ion beams at the Heidelberg Ion Therapy Center (HIT). By 2020, HIT will begin the first clinical raster-scanning particle therapy program using helium (4He) ions, which exhibit favorable biophysical properties intermediate of clinically used light and heavy ions. Today, a commercial treatment planning system (TPS) for 4He ions does not exist. This calls for an extensive development, testing and verification of a TPS for 4He ions, exploring both physical and biological dose models.This year, a GPU-based dose computation code for particle therapy (FRoG) was developed at HIT. Due to its parallelized computation scheme, sophisticated beam model and outstanding performance in conditions with anatomical complexity, FRoG performs forward dose calculations within minutes (in contrast to full simulation with hour-long runtimes) in excellent agreement with the clinical gold standard Monte Carlo simulations and measurements. Recent efforts focus on dose optimization (both physical and biological) for raster-scanning 4He ions beam therapy. A fully functional TPS within the FRoG framework will be devised and clinically integrated for 4He ion beams.Furthermore, biological phenomena of 4He ion beams remains poorly explored since the shutdown of clinical trials at the Lawrence Berkely National Laboratory in the early 1990u2019s. Potential biophysical and mechanistic approaches to modeling the relative biological effectives (RBE) in the clinic are under investigation in preparations for the first in-man treatment with raster-scanning 4He ion beams.