This article discusses the formation of fistulas in patients with intraductal papillary mucinous neoplasms (IPMN), a type of pancreatic tumor. The study found that fistula formation is more common in patients with a longer disease course and in those with main-duct or mixed IPMN. The most frequently involved organs in fistula formation are the stomach, bile duct, and duodenum. While fistula formation is not a surgical indication for IPMN, it should be considered based on the patient's overall condition and clinical symptoms. The article concludes by stating that the 5-year survival rates for IPMN with fistula formation are difficult to determine due to limited sample sizes and varied follow-up durations. [Extracted from the article]