We investigated a clinically viable QSI protocol in whole breast tumours excised from patients on a clinical scanner within a clinically feasible time frame. QSI has been largely limited to the preclinical setting, requiring strong gradients and a long acquisition time. We compared QSI against conventional DWI and DKI and found that diffusion indices across these techniques were consistent. Previous studies have shown that QSI provides a comprehensive characterisation of tissue microstructure, particularly in the presence of restricted diffusion. These results provide pivotal foundation for the clinical translation of QSI in breast cancer diagnosis and prognosis.