Abstract #3183

Moody J, McConville P, Rehemtulla A, Ross B, Elliott W, Leopold W, Moffat B, Lister R, Chenevert T

Diffusion MRI (dMRI) in oncology has demonstrated great promise as a biomarker for assessment of therapeutic efficacy. However, tumor heterogeneity can hinder consistent quantification of tumor response to therapy. We present here a novel approach to tumor characterization using dMRI which provides in vivo estimates of net tumor cell kill. Moreover, we demonstrate that dMRI-net kill is significantly correlated with conventional net kill derived from tumor growth delay, but was obtained more than seven weeks before conventional net kill was available. The use of diffusion MRI in preclinical drug development may significantly accelerate the in vivo evaluation of novel therapeutics.