The Role of DCE-MRI in Predicting Pathologic Complete Response After Neoadjuvant Chemotherapy in Rectal Cancer

Motivation: Neoadjuvant chemotherapy (NCT) benefits select locally advanced rectal cancer (LARC) patients, with those achieving clinical complete response (cCR) potentially avoiding surgery. Goal(s): To evaluate the efficacy of dynamic contrast-enhanced MRI (DCE-MRI) parameters and MRI tumor regression grade (MR-TRG) in predicting pathologic complete response (pCR) after NCT. Approach: Retrospective analysis of 81 rectal cancer patients, assessing DCE-MRI parameters and MR-TRG. Results: Ktrans and kep were significantly lower, while ve was higher in pCR patients, with AUCs of 0.763, 0.868, and 0.698, respectively. MR-TRG showed high specificity but limited sensitivity. Impact: This study highlights DCE-MRI's potential in noninvasively predicting complete response in rectal cancer, supporting personalized, less invasive management and enabling organ preservation strategies in responsive patients following neoadjuvant chemotherapy.