CTNNB1 and cancer: Those that may progress to cancer include intraductal papillary mucinous neoplasms (IPMNs), which typically harbor mutations in the GNAS, KRAS and RNF43 genes [5] and form in the main and branch ducts of the pancreas; mucinous cystic neoplasms (MCNs), which display mutations in RNF43 and KRAS and are typically solitary lesions that occur in the body or tail of the pancreas [5, 6]; and solid pseudopapillary neoplasms (SPNs), which show mutations in the CTNNB1 (beta-catenin) gene [5].