Dose prescription and optimisation based on tumour hypoxia

Area of Science:

• Radiation Oncology
• Medical Imaging
• Tumor Microenvironment

Background:

• Tumor hypoxia significantly contributes to radioresistance, diminishing radiotherapy efficacy.
• Advanced imaging techniques now allow for quantification of hypoxic regions, enabling targeted therapies.
• Developing methods to adapt radiation dose based on tumor oxygenation is crucial for improving treatment outcomes.

Purpose of the Study:

• To propose an objective method for prescribing radiation dose distributions that specifically target radioresistant hypoxic tumor regions.
• To evaluate the effectiveness of this method in simulations considering dynamic and heterogeneous tumor oxygenation.
• To assess the potential for sparing adjacent normal tissues through targeted dose delivery.

Main Methods:

• Development of an original method for objective prescription of dose distributions.
• Segmentation of dose distributions and optimization of prescribed doses to account for local oxygenation heterogeneity.
• Testing the method using clinically relevant simulations of dynamic and heterogeneous tumor hypoxia.

Main Results:

• Highly heterogeneous dose distributions showed improvements only for static oxygenation patterns.
• The proposed segmentation and optimization method significantly improved local control for clinically relevant, dynamic oxygenation patterns.
• The method demonstrated potential for sparing adjacent normal tissues by focusing dose on hypoxic regions.

Conclusions:

• The proposed method offers a significant improvement in local tumor control for heterogeneous and dynamic tumor hypoxia.
• This approach allows for objective dose prescription tailored to individual tumor oxygenation profiles.
• Clinical applicability is supported by its adaptability to functional imaging of tumor hypoxia.