Particle arc therapy is a new frontier of ion beam application to treat tumors. Moving away from the established particle therapy treatment regime that is constraint to few beam angles to arc irradiation, as is the state-of-the-art in photon
therapy, opens up new flexibility in healthy tissue sparing and maximizing biological effectiveness in the target. Carbon ion arcs, in particular, are a promising new strategy to boost the linear energy transfer in the target, overcoming hypoxia-induced radioresistance (Figure 1).

Within the Medical Physics group, we have developed bespoke treatment planning and delivery tools for advanced carbon ion arc therapy. Fast, robust treatment plannning for carbon ion arcs is implemented in TRiP98. A beam delivery simulation coupled to TRiP98 enables to investigate the impact of both dynamic carbon ion arcs delivery and anatomical motion. Further, we have developed the world-wide first dynamic carbon ion arc irradiation platform, that is fully integrated with a clinical dose delivery system in use at Centro Nazionale di Adroterapia Oncologia (CNAO), Pavia, Italy. This system has already permitted dosimetric assessment of carbon ion arc therapy in beam experiments at GSI, and is continuously improved together with our collaboration partners.
 
 Ongoing projects include:

• Carbon ion arc therapy delivery to patients in the upright position (UPLIFT, DC5)

• AI based arc energy selection for maximum treatment plan efficiency

• Combining intensity-modulated carbon ion therapy and carbon ion arcs for a simulataneous integrated boost against hypoxic malignancies

• Carbon ion arc therapy against multi

• Development of a dynamic