Time-dependent Magnetic Resonance Imaging for Predicting Pathological Complete Response in Rectal Cancer with Neoadjuvant Therapy

Motivation: Time-dependent (TD) magnetic resonance imaging (MRI), an emerging imaging modality, offers insights into cellular microstructures, but its relevance to rectal cancer's neoadjuvant treatment response remains unknown. Goal(s): To determine the value of TD MRI-derived metrics for preoperatively predicting pathological complete response (pCR) in rectal cancer. Approach: Univariate and multivariate logistic regression analyses were used to identify key predictors of pCR. Results: Extracellular diffusivity independently predicted pCR, with a cutoff of 1.640 effectively distinguishing between pCR and non-pCR tumors. Impact: Time-dependent magnetic resonance imaging emerges as a promising tool for detecting the pathological complete response in rectal cancer following neoadjuvant therapy, potentially facilitating the selection of patients who may benefit from a watch-and-wait approach.