1. The FRoG project
FRoG (Fast dose Recalculation on GPU) is a multi-ion analytical dose calculation engine developed in-house at the Heidelberg Ion Therapy Center (HIT, Heidelberg, Germany) and the National Centre of Oncological Hadrontherapy (CNAO, Pavia, Italy: fondazionecnao.it/en/). Platform features are presented in Fig. 1.
As opposed to conventional means used by the standard clinical TPS, FRoG’s enhanced computational power is conceived through task parallelization on a graphics processing unit (GPU). By design, FRoG is functional for all ions, both clinical (1H, 12C) and experimental (4He, 16O), available at HIT. For the four ions, physical dose, dose-averaged linear energy transfer (LETd) and various perspectives on the relative biological effectiveness (Fig. 2) are calculated simultaneously within minutes. Through user-friendly interface, physicians and physicists can better predict the “delivered biological dose” to the patient in challenging clinical cases, as well as incorporate LETd into treatment planning and clinical decision-making. On average, a dose calculation takes ~1 minute, enabling advanced computational studies, e.g. such as fast robustness analysis and clinical investigations with a large patient cohort, with minimal effort and within a reasonable timeframe.
With the upcoming clinical translation of therapeutic helium ion beams at the HIT by 2020, extensive development and verification of a treatment planning system (TPS) for helium ions (both physical and biological) must be completed prior to the first patients. Currently, there is no commercial TPS available for novel ions such as helium. FRoG stands as a strong candidate as a next-generation dose engine for both clinical and experimental beams.
S. Mein et al., “Fast robust dose calculation on GPU for high-precision 1H, 4He, 12C and 16O ion therapy: the FRoG platform,” Sci. Rep., 2018.
K. Choi et al., “FRoG—A New Calculation Engine for Clinical Investigations with Proton and Carbon Ion Beams at CNAO,” Cancers (Basel)., vol. 10, no. 11, p. 395, 2018.