Risk Assessment of Malignancy in Pancreatic Intraductal Papillary Mucinous Neoplasm Harboring Multiple Worrisome Features and High-Risk Stigmata: A Single-Center Cohort Study.

BACKGROUNDS: Pancreatic intraductal papillary mucinous neoplasm (IPMN) with multiple risk features, including worrisome features (WFs) and high-risk stigmata (HRS), may have a higher probability of malignant transformation. This study aimed to evaluate the risk of progressing to invasive carcinoma (IC) in IPMN patients. METHODS: This study collected data from IPMN patients who received regular monitoring at our hospital between June 2017 and January 2025, with a monitoring duration of more than 6 months. The changes in risk features and progression to IC during monitoring were recorded. RESULTS: IPMN patients with > 2 WFs or HRS had a higher probability of presenting with IC. Univariate and multivariate Cox regression analyses revealed that > 2 WFs (HR = 22.65, 95% CI: 4.28-119.83, p < 0.001) and HRS (HR = 17.39, 95% CI: 3.76-80.44, p < 0.001), family history of pancreatic carcinoma (HR = 5.35, 95% CI: 1.68-17.05, p = 0.005), serum carbohydrate antigen 19-9 (CA19-9) level (HR = 1.01, 95% CI: 1.01-1.01, p = 0.039), cyst growth rate (HR = 1.12, 95% CI: 1.06-1.19, p < 0.001), and main pancreatic duct (MPD) dilatation rate (HR = 1.26, 95% CI: 1.09-1.46, p = 0.002) were independent risk factors associated with malignant progression of IPMN. CONCLUSION: Intensified monitoring should be performed for IPMN patients carrying > 2 WFs or HRS. Discontinuation of surveillance should be carefully considered in patients without any risk features. Cyst growth rate and MPD dilatation rate are critical risk factors that require focused assessment during the monitoring of IPMN patients.