Mucinous Cystic Neoplasm : Molecular Pathology
Molecular Pathology of Mucinous Cystic Neoplasm (MCN) of Pancreas: The epithelial lining of MCNs shows activating point mutations in codon 12 of KRAS in 50-65% of cases. It considered to be an early event in the pathogenesis of MCN. Inactivation of TP53 and SMAD4 occur as late events. In addition, there are loss of function mutations in E3 ligase RNF43. Hypermethylation of CDKN2A has also been found in MCNs. These alterations are not unique to MCN and are found in other pancreatic epithelial tumors. The image shows classic histologic features of a MCN of pancreas, consisting of mucinous epithelium with underlying ovarian-type stroma.