Radioactive ion beam range adaptation in mouse tumors using in-beam PET

Area of Science:

• Medical Physics
• Radiation Oncology
• Nuclear Medicine

Background:

• Particle therapy requires precise range adaptation to avoid healthy tissue damage.
• In-beam positron emission tomography (PET) offers range verification but faces signal-to-noise and spatial mismatch challenges.

Purpose of the Study:

• To demonstrate real-time range adaptation using radioactive ion beams in a preclinical model.
• To evaluate the efficacy and safety of this novel approach for particle therapy.

Main Methods:

• Radioactive 11C ion beams were used for real-time range monitoring with an in-beam PET scanner.
• Range adaptation was performed using a remotely controlled range shifter in mice with osteosarcoma.
• Tumor growth, toxicity, and histological outcomes were assessed for different range settings.

Main Results:

• Spatially resolved PET signals correlated with biological outcomes.
• Adequate tumor coverage was achieved with adjusted ranges, while a short range led to continued tumor growth.
• Toxicity was observed only with the longest range setting.

Conclusions:

• In-beam imaging of radioactive ion beams enables real-time range-guided radiotherapy in vivo.
• Radioactive ion beams represent a promising platform for precision range-guided particle therapy.