Journal Article

GSI-2024-00630

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Relative biological effectiveness of oxygen ion beams in the rat spinal cord: Dependence on linear energy transfer and dose and comparison with model predictions

Glowa, C. ; Saager, M. ; Hintz, L. ; Euler-Lange, R. ; Peschke, P. ; Brons, S. ; Scholz, M.GSI* ; Mein, S. ; Mairani, A. ; Karger, C. P. (Corresponding author)

2024
Elsevier Science Amsterdam [u. a.]

Please use a persistent id in citations: doi:10.1016/j.phro.2024.100581  doi:10.15120/GSI-2024-00630

Abstract: Ion beams exhibit an increased relative biological effectiveness (RBE) with respect to photons. This study determined the RBE of oxygen ion beams as a function of linear energy transfer (LET) and dose in the rat spinal cord.The spinal cord of rats was irradiated at four different positions of a 6 cm spread-out Bragg-peak (LET: 26, 66, 98 and 141 keV/µm) using increasing levels of single and split oxygen ion doses. Dose-response curves were established for the endpoint paresis grade II and based on ED50 (dose at 50 % effect probability), the RBE was determined and compared to model predictions.When LET increased from 26 to 98 keV/µm, ED50 decreased from 17.2 ± 0.3 Gy to 13.5 ± 0.4 Gy for single and from 21.7 ± 0.4 Gy to 15.5 ± 0.5 Gy for split doses, however, at 141 keV/µm, ED50 rose again to 15.8 ± 0.4 Gy and 17.2 ± 0.4 Gy, respectively. As a result, the RBE increased from 1.43 ± 0.05 to 1.82 ± 0.08 (single dose) and from 1.58 ± 0.04 to 2.21 ± 0.08 (split dose), respectively, before declining again to 1.56 ± 0.06 for single and 1.99 ± 0.06 for split doses at the highest LET. Deviations from RBE-predictions were model-dependent.This study established first RBE data for the late reacting central nervous system after single and split doses of oxygen ions. The data was used to validate the RBE-dependence on LET and dose of three RBE-models. This study extends the existing data base for protons, helium and carbon ions and provides important information for future patient treatments with oxygen ions.

Keyword(s): Late normal tissue effects ; Linear energy transfer (LET) ; Local effect model (LEM) ; Modified microdosimetric kinetic model (mMKM) ; Myelopathy ; Oxygen ion radiotherapy ; Rat spinal cord ; Relative biological effectiveness (RBE)

Note: This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

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Contributing Institute(s):

1. Biophysik (BIO)
2. Collaboration FAIR: BIO (BIO@FAIR)

Research Program(s):

1. 633 - Life Sciences – Building Blocks of Life: Structure and Function (POF4-633) (POF4-633)
2. SUC-GSI-Heidelberg - Strategic university cooperation GSI-U Heidelberg (SUC-GSI-HE) (SUC-GSI-HE)

Experiment(s):

1. no experiment theory work (theory)

Appears in the scientific report 2024

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Database coverage:
; ; ; ; Article Processing Charges ; Clarivate Analytics Master Journal List ; DOAJ Seal ; Emerging Sources Citation Index ; Fees ; IF < 5 ; JCR ; PubMed Central ; SCOPUS ; Web of Science Core Collection

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