Analysis of tumour microstructure estimation from conventional diffusion MRI and application to skull-base chordoma

Area of Science:

• Neuro-oncology
• Medical Imaging
• Radiology

Background:

• Skull-base chordoma (SBC) is a rare tumor with incompletely understood molecular and radiological features.
• Diffusion-weighted MRI (DW-MRI) and its parameter, apparent diffusion coefficient (ADC), are widely used in neuro-oncology but lack clear microstructural links.
• ADC is a potentially valuable biomarker for tumor characterization.

Purpose of the Study:

• To derive microstructural information from conventional ADC values.
• To demonstrate the potential of ADC for characterizing skull-base chordomas.
• To correlate microstructural information with tumor cell proliferation.

Main Methods:

• Retrospective selection of 16 SBC patients who underwent conventional DW-MRI.
• Estimation of ADC maps from mono-exponential fits of DW-MRI data using various b-value sets.
• Simulation of DW-MRI signals from synthetic substrates mimicking tumor microstructure.
• Evaluation of an error-driven procedure to enhance microstructural parameter estimation.

Main Results:

• Quantitative microstructural description of SBC tumors derived from DW-MRI images.
• Successful differentiation of patients based on histologically verified cell proliferation information.
• Demonstration of ADC's capability to provide non-invasive microstructural insights.

Conclusions:

• Conventional ADC, when analyzed with advanced methods, can provide valuable non-invasive microstructural information about skull-base chordomas.
• This approach enables differentiation of tumors based on cell proliferation, potentially improving radiation treatment planning.
• The findings support the use of DW-MRI derived microstructure for personalized cancer management.