Real life management of intraductal papillary mucinous neoplasms of the pancreas: Final data from the prospective Italian pancreatic cysts (PANCY) registry

Background: Studies on surveillance of Intraductal Papillary Mucinous Neoplasms (IPMNs) are mainly retrospective with inherited bias. Aim: To identify factors associated with the development of relevant changes in low risk IPMN under surveillance. Methods: This study analysed IPMN patients enrolled between 2015–2017 in the prospective obser- vational multicentric registry PANcreatic CYsts (PANCY), focusing on brunch duct (BD).Extension of surveillance until December 31st, 2021 was proposed tothe recruited patients. Relevant changes were defined as: worrisome features/high risk stigmata/pancreatic cancer, pancreatectomy, death due to IPMN/pancreatic cancer.Results: At diagnosis, from 647 IPMNs, 547 (60%) were BD, 87 (9%) mixed type, and 13 (1%) main duct. 57 (8.8%) underwent immediate surgery and 590 (91.2%) active surveillance. Of them 34 (5.7%) underwent surgery with 2/3 malignancy. Malignancy rates for BD- and mixed-IPMNs under surveillance were 2.7% and 12.5%. Smoking (OR 2.2) and cyst size > 15 mm at diagnosis (OR 7.1) were independent risk factors for relevant changes at multivariate analysis. The combination of cyst size ≤15 mm & age > 65 was a protective factor at univariate analysis (OR 0.1), mainly in no smokers (OR 0.2, p < 0.01). Conclusions: BD-IPMN progression risk is low for lesions < 15 mm in non-smokers, > 65 years patients. Surgery and follow-up criteria are still imperfect, leading to inappropriate utilization of resources.