GNAS and pancreatic intraductal papillary-mucinous neoplasm: (iii) Molecular landscape: Compared with PDAC/IPMN, the classic pancreatic drivers KRAS, TP53, CDKN2A, SMAD4, GNAS, and RNF43 were less altered in ITPN (P < 0.001), whereas MCL amplifications, FGFR2 fusions, and PI3KCA mutations were commonly altered (P < 0.001).