KEY POINTS
- The European Particle Therapy Network was established in 2015 and became an ESTRO Task Force in 2017. By 2026, it had evolved into an interdisciplinary structure spanning clinical evidence, dosimetry, education, image guidance, treatment planning, radiobiology, health economics and registry infrastructure.
- European particle therapy has expanded substantially: by 2025, 30 clinical particle therapy facilities were operating across 15 countries, with carbon-ion therapy available at four centres. Access remains geographically uneven, particularly in Eastern and South-Eastern Europe.
- Harmonisation has been a major focus. A European QA survey across 34 institutions in 14 countries showed substantial variation in instrumentation, tolerances and workflows, prompting inter-centre benchmarking and guideline development for dosimetry, beam modelling and patient-specific QA.
- Clinical evidence generation is moving toward coordinated registries. EPTN has supported ParticleCARE and is now developing broader registry infrastructure through initiatives including KAYAC+, with nine participating centres and first patient data expected in 2026.
- Adaptive particle therapy has become a dedicated cross-network priority. The Adaptive Particle Therapy Task Group is developing common terminology, commissioning and QA guidance, imaging requirements, training standards and scalable clinical workflows.
- Future treatment-planning priorities include LET- and RBE-informed optimization, automated and AI-assisted planning, proton arc therapy and upright treatment, while radiobiology work aims to translate variable-RBE concepts into clinically usable guidance.
- Health economics remains a major unresolved issue. Limited randomized comparative data, inconsistent costing methodology and sparse quality-of-life information still restrict robust cost-effectiveness assessment; harmonisation with the ESTRO-HERO framework is now a stated priority.
CLINICAL TAKEAWAY
European particle therapy is entering a phase where expanding technology alone is no longer enough. EPTN’s next decade will focus increasingly on prospective evidence, common registries, harmonised QA, adaptive workflows and economic evaluation to define where particle therapy delivers clinically meaningful value.