Neon ion radiotherapy: physics and biology

Area of Science:

• Particle therapy
• Radiation oncology
• Medical physics

Background:

• Neon ion (20Ne) beam radiotherapy was explored in early clinical trials (1970s-1990s) at Lawrence Berkely National Laboratory (LBNL).
• Currently, therapeutic neon ion beams are exclusively available at the National Institutes for Quantum Science and Technology (QST) in Chiba, Japan.
• The first clinical multi-ion therapy (MIT) program at QST Hospital utilizes neon ion beams to escalate tumor radiation dose and linear energy transfer (LET).

Purpose of the Study:

• To review the technology, physics, radiobiology, and clinical applications of neon ion beams in particle therapy.
• To discuss the current status and future directions for neon ion beam therapy.
• To highlight the potential of neon ions and multi-ion mixtures for optimizing dose, LET, and relative biological effectiveness (RBE).

Main Methods:

• Comprehensive review of existing literature on neon ion beam technology and radiobiology.
• Analysis of clinical advancements, including high-precision scanning delivery techniques.
• Discussion of ongoing multi-ion therapy (MIT) clinical trials.

Main Results:

• Advancements in scanning delivery techniques allow for more targeted and safer neon ion treatments compared to historical methods.
• Neon ion beams and multi-ion mixtures offer greater flexibility in optimizing dose, LET, and RBE for cancer treatment.
• Pre-clinical investigations outside Japan are limited, necessitating more independent studies.

Conclusions:

• Neon ion therapy shows promise for treating certain malignancies by escalating LET within tumors.
• Limited availability and high costs currently restrict the widespread adoption of neon ion therapy.
• Future research should focus on technological developments, including novel delivery techniques like mini-beam and ultra-high dose rate therapies, to broaden clinical applicability.