3D analysis and evolution of prostate and tumor oxygenation using MRI-derived relative oxygen extraction fraction during MR-guided stereotactic body radiotherapy☆
- 1Radiation Oncology Department, Centre Hospitalier Lyon Sud, Hospices Civils de Lyon, France
- 2INSA-Lyon, Université Lyon 1, CNRS, Inserm, CREATIS UMR 5220, U1294, Lyon, France
- 3Department of Oncology Physics, Edinburgh Cancer Centre, Western General Hospital, Crewe Road South, Edinburgh, EH4 2XU, UK
Abstract
Background/Purpose Tumor hypoxia is a major cause of radioresistance, motivating the development of biomarkers related to tissue oxygen physiology that can be monitored throughout treatment. MRI-derived relative Oxygen Extraction Fraction (rOEF) is a non-invasive imaging biomarker related to tissue oxygen extraction. This study characterized the temporal evolution of rOEF during MR-guided stereotactic body radiotherapy (MRgSBRT) for prostate cancer. Materials/Methods Twenty-three prostate cancer patients treated with five-fraction MRgSBRT were analyzed. rOEF maps were acquired at treatment planning and at each treatment fraction. Average rOEF was extracted from the healthy prostate, gross tumor volume (GTV), and two gluteal muscle regions receiving either residual (in-field) or negligible (out-of-field) irradiation. Longitudinal changes in average rOEF and in the fraction of GTV voxels with rOEF >70% were quantified using patient-specific linear fits. Slopes of average rOEF in the healthy prostate were also calculated between successive imaging sessions. Results Average rOEF decreased significantly in all irradiated regions (healthy prostate, GTV and in-field gluteal muscle), with no significant change in the out-of-field gluteal muscle. The fraction of GTV voxels with rOEF >70% also declined significantly. In the healthy prostate, rOEF decreased predominantly during the first four fractions, with the steepest median slope observed between planning and the first treatment fraction (−3.2). Conclusions MRgSBRT was associated with a progressive reduction in rOEF confined to irradiated tissues, with the largest decrease in healthy prostate rOEF occurring after the first irradiation. These findings suggest rOEF could be a potential imaging biomarker of physiological changes associated with radiation exposure and warrant further investigation of its relationship with physiological processes and tissue hypoxia.
Related
- Efficacy and safety of single-fraction stereotactic body radiotherapy (SBRT) for the curative treatment of extracranial primary Tumors: A collaborative systematic review on behalf of the SBRT Focus Group of the European Society for Radiotherapy & Oncology (ESTRO).
- Dosimetric and Treatment Delivery Efficiency Comparison of Two Ring-gantry Linear Accelerator Platforms for Liver Stereotactic Body Radiotherapy
- Retrospective intrafraction motion verification using triggered kilovoltage images during bone metastases stereotactic body radiotherapy
- Characterization and Validation of MicroDiamond Detectors in Patient-specific Quality Assurance of Magnetic Resonance-guided Stereotactic Radiotherapy
- Dosimetric Comparison of Contemporary Stereotactic Radiotherapy Platforms for Brain Metastases: Towards Personalized Technology Selection
BibTeX
@article{berger2026analysis,
title = {{3D analysis and evolution of prostate and tumor oxygenation using MRI-derived relative oxygen extraction fraction during MR-guided stereotactic body radiotherapy☆}},
author = {Thomas Berger and Ariane Lapierre and Perla Zidane and Hayder Aloraibi and Samy Horn and Angela Boros and Frederic Cervenansky and Benjamin Leporq and Olivier Beuf and William Henry Nailon and Olivier Chapet},
journal = {Physics and imaging in radiation oncology},
year = {2026},
month = sep,
doi = {10.1016/j.phro.2026.101097},
url = {https://europepmc.org/article/PMC/PMC13660655},
note = {CC BY},
}
RIS
TY - JOUR
TI - 3D analysis and evolution of prostate and tumor oxygenation using MRI-derived relative oxygen extraction fraction during MR-guided stereotactic body radiotherapy☆
AU - Thomas Berger
AU - Ariane Lapierre
AU - Perla Zidane
AU - Hayder Aloraibi
AU - Samy Horn
AU - Angela Boros
AU - Frederic Cervenansky
AU - Benjamin Leporq
AU - Olivier Beuf
AU - William Henry Nailon
AU - Olivier Chapet
PY - 2026
DA - 2026/09/01
JO - Physics and imaging in radiation oncology
DO - 10.1016/j.phro.2026.101097
UR - https://europepmc.org/article/PMC/PMC13660655
AB - Background/Purpose Tumor hypoxia is a major cause of radioresistance, motivating the development of biomarkers related to tissue oxygen physiology that can be monitored throughout treatment. MRI-derived relative Oxygen Extraction Fraction (rOEF) is a non-invasive imaging biomarker related to tissue oxygen extraction. This study characterized the temporal evolution of rOEF during MR-guided stereotactic body radiotherapy (MRgSBRT) for prostate cancer. Materials/Methods Twenty-three prostate cancer patients treated with five-fraction MRgSBRT were analyzed. rOEF maps were acquired at treatment planning and at each treatment fraction. Average rOEF was extracted from the healthy prostate, gross tumor volume (GTV), and two gluteal muscle regions receiving either residual (in-field) or negligible (out-of-field) irradiation. Longitudinal changes in average rOEF and in the fraction of GTV voxels with rOEF >70% were quantified using patient-specific linear fits. Slopes of average rOEF in the healthy prostate were also calculated between successive imaging sessions. Results Average rOEF decreased significantly in all irradiated regions (healthy prostate, GTV and in-field gluteal muscle), with no significant change in the out-of-field gluteal muscle. The fraction of GTV voxels with rOEF >70% also declined significantly. In the healthy prostate, rOEF decreased predominantly during the first four fractions, with the steepest median slope observed between planning and the first treatment fraction (−3.2). Conclusions MRgSBRT was associated with a progressive reduction in rOEF confined to irradiated tissues, with the largest decrease in healthy prostate rOEF occurring after the first irradiation. These findings suggest rOEF could be a potential imaging biomarker of physiological changes associated with radiation exposure and warrant further investigation of its relationship with physiological processes and tissue hypoxia.
SN - 2405-6316
ER -