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Recently we showed that MRI using a new lymph-node contrast (gadofosveset) has high accuracy for nodal staging in rectal cancer. Aim of this study was to determine the most accurate imaging criteria for nodal evaluation on gadofosveset-MRI.Thirty-three patients underwent T1-weighted MRI before and after administration of gadofosveset-contrast. For each node the signal intensity (SI) was measured onpre-and post-contrast MRI. Furthermore, thepresence of a nodal relief effect was scored. Finally, nodes were scored (using a 5-point confidence score) by an MR-rectum expert, based on visual evaluation of SI and nodal relief. Nodes were drawn on an anatomical template for lesion-by-lesion histologic validation.Two hundred and eighty-nine nodes (55 malignant) were analysed. Onpre-contrast MRI, SI did not differ between benign and malignant nodes. On gadofosveset-MRI, SI was significantly higher in the benign nodes (P < 0.0001), which resulted in an area under the ROC-curve (AUC) of 0.74. The combination of SI and nodal relief rendered an AUC of 0.88. When analysed visually, AUC for discrimination of metastatic nodes was 0.92.Only benign nodes show uptake of gadofosveset-contrast. The best criteria are nodal signal intensity and relief. When analysed visually, these criteriaprovide high accuracy for discrimination of metastatic nodes.