Methodology for quantifying interactions between perfusion evaluated by DCE-US and hypoxia throughout tumor growth

Area of Science:

• Oncology
• Medical Imaging
• Physiology

Background:

• Tumor microenvironment characterization is crucial for understanding cancer progression.
• Dynamic contrast-enhanced ultrasonography (DCE-US) and oximetry are emerging technologies for assessing tumor physiology.
• Spatio-temporal monitoring of tumor perfusion and oxygenation remains a challenge.

Purpose of the Study:

• To validate a combined DCE-US and oximetry methodology for evaluating tumor physiology.
• To assess the temporal and spatial dynamics of tumor perfusion and oxygenation in a preclinical model.
• To investigate the correlation between tumor perfusion and intratumoral oxygen partial pressure (pO2).

Main Methods:

• Human prostate cancer xenografts in mice were studied over three weeks.
• Dynamic contrast-enhanced ultrasonography (DCE-US) was used to quantify tumor perfusion via time-intensity curves in defined regions-of-interest (ROIs).
• An ultrasound-guided oximeter probe measured pO2 in specific tumor areas, with no observed impact on tumor growth.

Main Results:

• Significant variations in perfusion and oxygenation were observed in the central tumor region.
• A significant correlation (p = 0.0068; r = 0.66) was found between local central tumor perfusion and pO2.
• Both perfusion and pO2 demonstrated a decreasing trend over the experimental period.

Conclusions:

• The developed methodology effectively combines DCE-US with direct tissue pO2 measurements.
• This combined approach enhances the description of complex intratumoral dynamic behaviors.
• The study highlights the potential of integrated imaging and sensing for preclinical cancer research.