Risk factors for intraductal papillary mucinous neoplasm (IPMN) of the pancreas: a multicentre case-control study

OBJECTIVES: To investigate environmental, personal, and hereditary risk factors associated with the occurrence of intraductal papillary mucinous neoplasms of the pancreas (IPMNs). METHODS: Multicentre case–control study. Risk factors were identified from a questionnaire collecting data on family and medical history, and environmental factors. Cases were prevalent IPMNs seen at the participating units within an 18-month timeframe. Matched controls were enrolled alongside patients seen at outpatient clinics. RESULTS: Three-hundred and ninety patients with IPMN and 390 matched controls (166 males, mean age 65 in each group) were enrolled. Of the IPMNs, 310 had branch-duct involvement and 80 main-duct involvement. The only cancer with a 1st degree family history significantly higher in IPMN was pancreatic ductal adenocarcinoma (PDAC) (5.4% vs. 1.5%). Previous history of diabetes (13.6% vs. 7.5%), chronic pancreatitis (CP) (3.1% vs. 0.3%), peptic ulcer (7.2% vs. 4.3%), and insulin use (4.9% vs. 1.1%) were all more frequent with IPMNs. Logistic regression multivariate analysis revealed that history of diabetes (odds ratio (OR): 1.79, confidence interval (CI) 95%: 1.08–2.98), CP (OR: 10.10, CI 95%: 1.30–78.32), and family histories of PDAC (OR: 2.94, CI 95%: 1.17–7.39) were all independent risk factors. However, when analysis was restricted to diabetics who had taken insulin, risk of IPMN became stronger (OR: 6.03, CI 95%: 1.74–20.84). The association with all these risk factors seemed stronger for the subgroup with main duct involvement. CONCLUSIONS: A previous history of diabetes, especially with insulin use, CP, and family history of PDAC are all relevant risk factors for the development of IPMN. These results suggest an overlap between certain risk factors for PDAC and IPMN.