GNAS and cyst: In a recent multi-center, retrospective study of 130 patients with resected pancreatic cystic neoplasms, cyst fluid was analyzed to identify mutations in genes known to be mutated in pancreatic cystic neoplasms (BRAF, CDKN2A, CTNNB1, GNAS, KRAS, NRAS, PIK3CA, RNF43, SMAD4, TP53, and VHL) [41].