Synopsis

Keywords: Body: Digestive

Rectal MR is central to the management of rectal cancer patients, driving management at initial presentation and after neo-adjuvant therapy. After neoadjuvant therapy at re-staging MRI, the issue of residual tumor versus post treatment fibrosis is of primary importance where ‘watch and wait’ without surgical resection is possible for a complete clinical response. Optimizing the MR protocol, including the addition of intra-rectal gel, can improve both T2W and DWI images which are core to distinguishing between residual tumor and fibrosis. In addition, knowledge of lymph node drainage patterns can augment the accuracy of lymph node status.