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Updated: Jun 8, 2026
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Live Imaging to Quantify Cellular Radiosensitivity in Patient-Derived Tumor Organoids
Published on: April 5, 2024
ADC response to radiation therapy correlates with induced changes in radiosensitivity
Matthew P Larocque1, Alasdair Syme, Joan Allalunis-Turner
1Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2, Canada.
Medical Physics
|September 14, 2010
Summary
Inducing ischemia with a ligature altered tumor radiosensitivity. Magnetic resonance imaging showed reduced apparent diffusion coefficient (ADC) response to radiation in ligated human glioma xenografts, indicating biological factors influence treatment outcomes.
Area of Science:
- Radiology and Oncology
- Medical Imaging
- Cancer Research
Background:
- Radiosensitivity is crucial for effective radiation therapy in gliomas.
- Understanding factors influencing radiosensitivity can optimize treatment strategies.
- Magnetic resonance imaging (MRI) offers non-invasive monitoring of tumor response.
Purpose of the Study:
- To investigate the impact of induced ischemia on the radiosensitivity of human glioma xenografts.
- To compare MRI-derived parameters (ADC and T2) in response to radiation with and without ischemia.
Main Methods:
- Human glioma xenografts in mice were subjected to ischemia via a suture ligature.
- Tumors were irradiated (800 cGy) with or without the ligature in place.
- Apparent diffusion coefficient (ADC) and transverse relaxation time (T2) were measured using MRI before and after treatment.
Main Results:
- Ischemia alone caused a temporary decrease in tumor T2 but did not affect ADC.
- Irradiation with a ligature resulted in a significantly smaller increase in tumor ADC (9.6%) compared to non-ligated tumors (21.8%).
- This suggests altered radiosensitivity due to ischemia.
Conclusions:
- Tumor response to radiation therapy, as measured by ADC, is influenced by radiosensitivity and biological factors, not solely by radiation dose.
- Induced ischemia can modulate the biological response of gliomas to radiation.
- MRI parameters like ADC can reflect these radiosensitivity changes.
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