KRAS and pancreatic neoplasm: Regarding the relevance of the Ptf1aCre/+;LSL-KrasG12D/+ mouse strain as a model for human pancreatic cancer development, it should be noted that Kras mutations have been reported to be present in >90% of human pancreatic adenocarcinomas and found in more than 95% of the earliest pre-cancerous PanIN-1 features [8].