Reproducible radiomic features from post-chemoradiation T2-weighted MRIs can more accurately discriminate pathologic T stage in rectal cancer patients

We present initial results for identifying radiomic features to effectively characterize pathologic chemoradiation response in rectal cancers, by ensuring feature reproducibility within reference non-tumor regions on post-chemoradiation T2w MRIs. Our approach used a new feature reproducibility measure to prune radiomic features and thus minimize variability due to acquisition or imaging differences. Microscale gradient radiomic features were found to be most reproducible and discriminable in segregating rectal cancer patients by post-chemoradiation pathologic stage independent of disease metastasis, across both training (AUC=0.75) and hold-out validation (accuracy = 84.6%) cohorts.