ABSTRACT
Conventional imaging techniques, digital rectal examination, and endoscopy previously used to predict the efficacy of neoadjuvant chemoradiation for treating rectal cancer are mainly based on the morphological information of tumors, but their treatment efficacy was not satisfying. In comparison, functional parameters are added into functional imaging and radiomics technologies such as diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE-MRI), and positron emission computed tomography (PET-CT) based on the morphological information of tumors. These technologies cover rich biological information of tumors and can reflect the efficacy of neoadjuvant chemoradiotherapy of rectal cancer patients before the morphology of tumors changes. This paper reviews the progress made in predicting the efficacy of neoadjuvant chemoradiation for treating rectal cancer using functional imaging and radiomics technologies.