DWI Parameters Correlated with Ki-67 Expression, a Prognostic Biomarker, in a Triple-Negative Breast Cancer PDX Mouse Model

Motivation: The lack of reliable biomarkers for assessing tumor characteristics and the limitations of histological analysis due to tumor heterogeneity led to the exploration of diffusion-weighted parameters. Goal(s): To investigate the association between DW parameters and Ki-67 expression in triple-negative breast cancer, with a focus on whether they can serve as prognostic biomarkers. Approach: Seventeen triple-negative breast cancer mice with a PDX model underwent 7T MRI scans, yielding DW images. Advanced analysis evaluated ADC and non-Gaussian diffusion parameters, validated through histological Ki-67 staining. Results: DWI parameters (S-index, sADC, and ADC0) show strong correlations with Ki67 levels, at short and long diffusion times (9, 27.6ms). Impact: Promising prognostic biomarkers for triple-negative breast cancer, DWI parameters (S-index, sADC, and ADC0) displayed strong correlations with Ki-67 expression, at short and long diffusion times. This validation through accurate DWI-pathology comparison highlights imaging's pivotal role in advancing breast cancer diagnosis.