Parametric Response Mapping: A Voxel-Based Analysis of Quantitative Diffusion MRI Changes for Individualized Assessment of Primary Breast Cancer Response to Therapy

Chuck Meyer¹, Thomas Chenevert, Craig Galban, Timothy Johnson, Daniel Hamstra, Alnawaz Rehemtulla, Brian Ross

This paper presents preliminary evidence supporting feasibility of using three ADC MRI interval acquisitions, two pre- and one post-therapy initiation to determine response to neoadjuvant chemotherapy within two weeks. This was a double blinded study where the clinical oncologists clinical assessment of response to the first cycle of chemotherapy was compared to quantitative estimates of increased intra-tumoral diffusion. The use of parametric response mapping (PRM), a voxel-by-voxel change analysis, demonstrated 100% accuracy in the initial feasibility study of 5 primary breast cancer patients.