Interestingly, KRAS, RNF43 and GNAS mutation were more frequent in type 1 than type 2, reflecting that these mutations are more importantly related genetic changes of IPNB with respect to the tumorigenesis maintaining similarities to IPMN and/or lower aggressive characters of IPNB. This evidence concerns the gene GNAS and pancreatic intraductal papillary-mucinous neoplasm.