The most common types of PCNs (Figure 1) are mucin-producing intraductal papillary mucinous neoplasms (IPMNs, encompassing branch-duct IPMNs, main-duct IPMNs and mixed-type IPMNs) and mucinous cystic neoplasms (MCNs). This evidence concerns the gene MUC5AC and lipoid nephrosis.