Carcinoembryonic antigen-related cellular adhesion molecule 6 (CEACAM6), which has been reported as a possible biomarker in IPMN and cholangiocarcinoma, was highly up-regulated in PB but not INT IPMN (Fig. 5B) (21, 37). Here, CEACAM6 is linked to pancreatic intraductal papillary-mucinous neoplasm.