Diffusion-Weighted MRI for the Early Response Assessment of Neoadjuvant Chemotherapy in Breast Cancer: Does Perfusion Effect Influence ADC Map Accuracy?

David Garbera¹, Jyoti Parikh², Geoffrey David Charles-Edwards³

We analyse use of diffusion-weighted MRI (DWI) scanning, and generation of apparent diffusion coefficient (ADC) maps, in predicting early response to neoadjuvant chemotherapy (NACT) in patients with breast cancer. It is thought that perfusion effects may confound accuracy of ADC values calculated from DWI. We gathered mean ADC values from pre and mid-treatment scans by generating a region of interest around a whole lesion. Early changes in mean ADC value were correlated with eventual radiological response to NACT. Early change in mean ADC value performed better than long-axis measurements in predicting response. Only ADC maps excluding perfusion were significantly better.