Risk of additional pancreatic cancer in patients with branch duct intraductal papillary-mucinous neoplasm.

Branch duct intraductal papillary-mucinous neoplasms of the pancreas (BD-IPMN) are being diagnosed with increasing frequency. Although BD-IPMN outcomes are generally good, pancreatic ductal adenocarcinoma (PDA) is found distant from the original BD-IPMN in about 3.3-9.2% of cases. These reports raise the question of whether a possible association exists between BD-IPMN and PDA. Recent findings from follow-up studies suggest that pancreases with BD-IPMNs have a high risk of developing additional pancreatic cancer, with standardized incidence ratios (SIRs) of 15.8- to 26-fold. These studies suggest that special attention should be paid to BD-IPMN patients who are ≥70 years. Furthermore, molecular evidence supports the hypothesis that field cancerization causing multiple primary neoplastic lesions exists in pancreases harboring IPMNs. Although more extensive studies are required to clarify the magnitude of this increased risk, clinicians should pay close attention to the development of PDA in patients with BD-IPMN, as well as to changes in BD-IPMN lesions.