Dynamic changes in main pancreatic duct (MPD) diameter are key in predicting malignancy risk for patients with MPD-involved IPMN.

• In a study of 168 patients, 17.8% developed malignancy over a median of 4 years, with an annual incidence of 4.5%.
• An MPD growth rate of ≥ 2 mm/year emerged as the strongest predictor, with a staggering odds ratio of 33.0 (p < 0.001).

Focus on MPD monitoring can guide timely surgical interventions, enhancing patient outcomes.

• Cumulative malignancy incidences were 7.7% at 2 years, 14.3% at 4 years, and 14.9% at 6 years.