Described for the first time in 1982 by Ohhashi K et al. as neoplasm with mucin hyperproduction, dilation of the duct of Wirsung and protruding papilla (the Ohhashi triad), intraductal papillary mucinous neoplasms (IPMNs) were more specifically described in 1996 by the WHO as: “neoplasm covered with columnar cells containing high mucin with or without papillary projections, involving the main pancreatic duct and/or secondary ducts without an ovarian stroma”. This evidence concerns the gene MUC5AC and neoplasm.