Tobias Baumann1, Markus Treier1, Axel zur Hausen2, Matthias Langer1, Arnd-Oliver Schfer1
1Department of Diagnostic Radiology, University Hospital Freiburg, Freiburg, Germany; 2Department of Pathology, University Hospital Freiburg, Freiburg, Germany
Circumferential resection margin (CRM), T-stage and nodal stage are the most important factors influencing therapy and outcome in rectal cancer, but the optimal imaging protocol to accurately assess these image features is yet under debate. In this study we therefore sought to evaluate thin-slice, high-resolution pelvic MRI with 3D sequences with a focus on detection of nodal disease and the diagnostic value of contrast enhanced imaging. T-staging strongly depended on reader experience and prior neoadjuvant therapy reduced the accuracy of MRI. A combination of morphologic criteria from T2 and contrast enhanced sequences yielded the highest accuracy for nodal staging.