A groundbreaking research project has unveiled a new strategy that improves the treatment of large sacral chordomas through carbon ion therapy. This study emphasizes optimizing dose-averaged linear energy transfer (LETd), a pivotal factor in radiotherapy that enhances treatment effectiveness for difficult tumours. Published in Medical Physics, these findings have the potential to greatly influence patient outcomes against these aggressive and resilient cancers.
Carbon ion therapy is a precise cancer treatment harnessing the unique physical and biological attributes of carbon ions. Although traditionally effective with smaller tumours, its potency diminishes with larger targets due to lower LETd distribution, reducing treatment efficacy. Addressing this issue, researchers from MedAustron Ion Therapy Center and Karl Landsteiner University of Health Sciences (KL Krems) utilized advanced treatment planning system (TPS) functionalities in a recent study.
“Our study reveals that optimizing LETd distribution significantly boosts the biological effectiveness of carbon ion therapy in large tumours, such as sacral chordomas, without sacrificing safety or precision,” explains Prof. Markus Stock. He is the senior author of the study, heading the Division of Medical Physics focused on Particle Therapy at KL Krems, and leading the Medical Physics department at MedAustron.
The research conducted a comparison of conventional and LETd-optimized plans for substantial tumours larger than 250 cm³, and highlighted several important findings:
- Increased LETd concentration: Up to 34% higher LETd in tumours, enhancing high-energy ion interactions exactly where they’re most required.
- Safety for surrounding tissues maintained: Effective safeguarding of key organs like the bowel, nerves, and spinal cord was achieved.
- Minimal impact on procedural efficiency: Optimization introduced negligible delays to planning and delivery.
Collaborating with Prof. Piero Fossati, the team utilized state-of-the-art LETd optimization integrated into the RayStation TPS for radiation therapy. This ensured comprehensive dose coverage while adapting high-LET zones to resistant tumour regions.
These advancements offer new hope for patients with large, previously challenging tumours to treat. “Large chordomas often lead to subpar clinical outcomes due to their size and closeness to critical organs,” explains Dr. Mansure Schafasand, first author and colleague of Prof. Stock. “Our optimized planning strategy is a crucial stride towards enhancing survival rates and life quality for these patients.”
The study highlights the importance of LETd as a success indicator in treatment, aligning with recent “LET painting” research that involves selectively modulating LET levels within tumours to target resistant regions. The collaborative effort by researchers at KL Krems and MedAustron paves the way for expanded applications in carbon ion therapy and may inspire future research into personalized and adaptive radiotherapy techniques. It spotlights KL Krems’ dedication to contributing relevant clinical research that enhances patient quality of life.
Karl Landsteiner University of Health Sciences (KL Krems) is a European-recognized hub for education and research located on Campus Krems. KL Krems offers contemporary, demand-focused education in medicine and psychology, alongside a PhD program in mental health and neuroscience.