A radiologist (A.N., 18 years experience in abdominal imaging) analysed all USPIO-enhanced MRI images. A second radiologist (J.H., 23 years experience in pancreatic imaging) supervised the analysis. Disagreements were resolved in a consensus meeting. Both radiologists were blinded to the histopathology results. All visible LNs, regional and distant, were annotated and measured (short axis on axial orientation). LN locations were indicated using the classification of the Japan Pancreas Society [18] . LNs were scored on the iron-sensitive T2*-weighted mGRE (TE = 12 ms) sequence, using diagnostic guidelines adapted from Anzai et al (Table 2, [19] ). Type 1-4 LNs were classified as suspicious for metastases and type 5-7 LNs as non-suspicious. The distinction between regional and distant LNs was based on the TNM classification (eighth edition) by the UICC [5] . The definition of regional nodes differs depending on the cancer type (pancreatic head or tail, cholangial, ampullary, or duodenal), the respective definition for each tumour type was applied.