KRAS and pancreatic ductal adenocarcinoma: In contrast to IPMNs which show KRAS-Mutations in approximately 60% of cases and ductal adenocarcinoma of the pancreas which shows KRAS mutations in almost all cases [15], no KRAS mutations were observed in a series of 24 ITPNs with invasive (n = 13) or non-invasive tumor growth (n = 11).