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Updated: Feb 9, 2026
08:17
Dynamic Lung Tumor Tracking for Stereotactic Ablative Body Radiation Therapy
Published on: June 7, 2015
16.2K
18F-EF5 PET-based Imageable Hypoxia Predicts Local Recurrence in Tumors Treated With Highly Conformal Radiation
Yushen Qian1, Rie Von Eyben1, Yufei Liu1
1Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California.
Summary
Tumor hypoxia, detected by 18F-EF5 PET imaging, was found in 43% of patients. Hypoxic tumors showed a higher rate of local recurrence after radiation therapy, highlighting its prognostic value.
Area of Science:
- Oncology
- Radiology
- Nuclear Medicine
Background:
- Tumor hypoxia is a known factor in radiation resistance.
- Noninvasive assessment of tumor hypoxia can aid in prognostication and treatment selection.
- 18F-EF5 PET is a promising imaging agent for hypoxia, but its clinical outcome correlation needs further study.
Purpose of the Study:
- To evaluate the correlation between imageable tumor hypoxia using 18F-EF5 PET and clinical outcomes after radiation therapy.
- To assess the feasibility of functional manipulation of tumor oxygenation in conjunction with 18F-EF5 PET imaging.
Main Methods:
- 28 patients with localized tumors received pretreatment 18F-EF5 PET.
- Tumor oxygenation was manipulated with carbogen breathing or dichloroacetate in some patients, followed by repeat PET.
- Imageable hypoxia was defined by 18F-EF5 uptake, and its correlation with local recurrence was analyzed using Cox models.
Main Results:
- Imageable hypoxia was present in 43% of patients at baseline.
- Carbogen breathing reduced imageable hypoxia, while dichloroacetate did not significantly alter it.
- Tumors with imageable hypoxia had a significantly higher local recurrence rate (30%) at 12 months compared to non-hypoxic tumors (0%).
Conclusions:
- Noninvasive 18F-EF5 PET imaging can identify tumor hypoxia in a significant portion of patients.
- Imageable hypoxia is associated with an increased risk of local tumor recurrence following radiation therapy.
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