With the upcoming RayStation release*, RaySearch introduces enhanced support for reirradiation planning and evaluation. The new framework includes cumulative dose assessment based on deformable image registration and equieffective dose in 2 Gy fractions (EQD2). The framework enables ROI‑specific EQD2 parameters, including the modeling of partial tissue recovery between treatment courses.
Because reirradiation is fundamentally constrained by cumulative dose to organs at risk (OARs), particle therapy is particularly well suited for these scenarios. Its ability to reduce unnecessary dose to previously irradiated tissues helps mitigate the risk of severe toxicity, even in complex reirradiation cases. Reflecting this, RayStation supports reirradiation planning across modalities – including all currently supported delivery techniques for proton, helium, and carbon ion therapy – regardless of the modality used in prior treatments.
To further strengthen particle therapy in reirradiation, RayStation enables robust optimization of cumulative EQD2, allowing direct consideration of prior OAR doses in the optimization process. This can be combined with conventional robust optimization for the reirradiation target, accounting only for the dose contribution from the current plan. Together, these capabilities support a balanced and clinically relevant trade‑off between cumulative OAR doses and target coverage.
*This functionality is investigational, not CE‑marked or FDA‑cleared, and is not available for clinical use.