Related Experiment Video
Updated: Dec 3, 2025
Proton Therapy Delivery and Its Clinical Application in Select Solid Tumor Malignancies
Published on: February 6, 2019
Unresectable Chondrosarcomas Treated With Carbon Ion Radiotherapy: Relationship Between Dose-averaged Linear Energy
Shinnosuke Matsumoto1, Sung Hyun Lee2, Reiko Imai3
1Department of Accelerator and Medical Physics, National Institute of Radiological Sciences, Quantum Medical Science Directorate, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan matsumoto.shinnosuke@qst.go.jp.
Background/Aim:
The local control rate of chondrosarcomas treated with carbon-ion radiotherapy (CIRT) worsens as tumour size increases, possibly because of the intra-tumoural linear energy transfer (LET) distribution. This study aimed to evaluate the relationship between local recurrence and intra-tumoural LET distribution in chondrosarcomas treated with CIRT.
Patients And Methods:
Thirty patients treated with CIRT for grade 2 chondrosarcoma were included. Dose-averaged LET (LETd) distribution was calculated by the treatment planning system, and the relationship between LETd distribution in the planning tumour volume (PTV) and local control was evaluated.
Results:
The mean LETd value in PTV was similar between cases with and without recurrence. Recurrence was not observed in cases where the effective minimum LETd value exceeded 40 keV/μm.
Conclusion:
LETd distribution in PTV is associated with local control in chondrosarcomas and patients treated with ion beams of higher LETd may have an improved local control rate for unresectable chondrosarcomas.
