Classification of HER2-zero and HER2-low and Prediction of Progression in Triple Negative Breast Cancer Using MRI Features

Motivation: Triple-negative breast cancer (TNBC) is more aggressive than other molecular subtypes, and finding new biomarkers for targeted therapy and stratification of progression risk would be helpful. Goal(s): To evaluate MRI features between HER2-zero and HER2-low, and between progressed vs. non-progressed TNBC patients. Approach: MRI features were reviewed by radiologists based on BI-RADS lexicon. Results: 85/126 (67%) were identified as HER2-zero and 41 (33%) as HER2-low. No MRI features showed a significant difference between HER2-zero vs HER2-low. Fourteen of 126 (11%) patients showed progression (local, regional progression or distant metastasis), and they have more aggressive finding features and higher stages. Impact: TNBC had negative ER, PR, and HER2, which was defined as immunohistochemical staining 0, 1+, or 2+ with negative FISH, but currently, HER2-low may receive anti-HER2 drug conjugates. Finding imaging biomarkers may help in precision treatment and understanding progression risk.