The value of quantitative synthetic MRI in differentiating breast cancer patients with HER2 zero-, low- and over-expressing

Motivation: Half of breast cancers exhibits HER2 low-expressing and benefits from new antibody-drug conjugates. However, it remains lack of non-invasive technique to identify HER2 expression level. T1, T2, and proton density (PD) are quantitative MRI parameters widely used to characterize tumors. Goal(s): Investigate if T1, T2, and PD extracted from synthetic MRI (syMRI) can be used to classify HER2 expression level. Approach: One-hundred patients were enrolled. T1, T2, and PD of tumor were extracted from syMRI and were compared among different HER2 expression level. ROC was used to assess the diagnostic performance. Results: T1 and PD can be used to diagnose HER2 expression levels. Impact: Our results suggested quantitative SyMRI can be used as non-invasive biomarker to classify HER2 zero-, low- and over-expressing breast cancer patients. It would be helpful in guiding treatment selection and dynamically monitoring HER2 expressing status during treatment process over time.