Pulse Radiolysis Using Very-high-energy Ions for Optimizing Cancer Therapy

Area of Science:

• Medical physics
• Radiation chemistry
• Particle physics

Background:

• High-energy ion cancer therapy offers high efficiency due to the linear-energy-transfer effect, minimizing unwanted side reactions from free radicals.
• Positrons (e⁺) and gamma rays generated during ion interactions are used for radiation dose monitoring in tumors.
• Thermalized positrons can become solvated (e⁺aq) or form positronium (Ps), leading to longer lifetimes and potential side reactions.

Purpose of the Study:

• To investigate and understand the reaction mechanisms involving positrons in high-energy ion cancer therapy.
• To propose and evaluate a novel time-resolved pulse radiolysis instrument for improved cancer treatment monitoring.
• To enhance the precision and efficacy of radiation therapy through a deeper comprehension of particle interactions.

Main Methods:

• Utilizing a time-resolved pulse radiolysis instrument designed for high-energy particle interactions.
• Employing positrons (e⁺) and gamma rays as probes for radiation dose monitoring.
• Analyzing the behavior of solvated positrons (e⁺aq) and positronium (Ps) in biological media.

Main Results:

• The study discusses a proposed time-resolved pulse radiolysis instrument for analyzing positron interactions.
• The instrument is designed to provide insights into side reactions initiated by solvated positrons (e⁺aq) and positronium (Ps).
• The method has been examined and recommended by CERN experts for its potential in radiation therapy.

Conclusions:

• A better understanding of reaction mechanisms is crucial for optimizing high-energy ion cancer therapy.
• The proposed time-resolved pulse radiolysis instrument offers a promising approach to monitor and control radiation therapy processes.
• Implementation at the MedAustron Radiation Therapy and Research Centre is planned to advance cancer treatment research.