Multimodal Functional Imaging for Cancer/Tumor Microenvironments Based on MRI, EPRI, and PET

Area of Science:

• Oncology
• Medical Imaging
• Radiotherapy

Background:

• Radiation therapy is a primary cancer treatment.
• Tumor response is affected by the tumor microenvironment, including hypoxia and redox status.
• Visualizing this microenvironment is crucial for treatment planning and early detection.

Purpose of the Study:

• To review functional imaging techniques for visualizing the tumor microenvironment.
• To highlight the potential of multimodal imaging for cancer theranostics.

Main Methods:

• Positron Emission Tomography (PET)
• Electron Paramagnetic Resonance (EPR) oxygen mapping
• Dynamic Nuclear Polarization (DNP) MRI
• Blood Oxygen Level Dependent (BOLD) MRI
• Tissue Oxygen Level Dependent (TOLD) MRI
• EPR imaging (EPRI)
• ¹³C-DNP MRI

Main Results:

• Tumor hypoxia can be sensed by PET, EPR, and DNP MRI.
• Oxygenation and redox status can be visualized using BOLD/TOLD MRI and EPRI.
• ¹³C-DNP MRI visualizes tumor glycometabolism.
• Co-registration of multimodal images clarifies biological effects and drug mechanisms.

Conclusions:

• Functional imaging techniques converge on theranostics.
• Multimodal imaging instruments like PET-MRI can integrate multiple functions.
• Visualizing the tumor microenvironment enhances radiotherapy and cancer detection.