Primary tumour response on breast MRI as a predictor of axillary pathologic response in breast cancer patients treated with neoadjuvant chemotherapy

Question Accurate non-invasive methods to differentiate between patients with and without axillary pathologic complete response after neoadjuvant chemotherapy prior to axillary surgery are currently lacking. Findings Breast complete response on MRI after neoadjuvant chemotherapy indicates a low probability (< 10%) of axillary residual disease in clinically node-negative patients and oestrogen receptor-negative tumours. Clinical relevance Breast complete response on MRI may be a non-invasive, clinically useful tool to exclude patients with axillary residual disease after neoadjuvant chemotherapy prior to axillary surgery and guide patient selection for potential de-escalation of axillary treatment.