Pancreatic Cancer is More Frequently Early Stage at Diagnosis in Surgically Resected Intraductal Papillary Mucinous Neoplasms With Preoperative Surveillance.

ABSTRACT

Background and Aims: Management of intraductal papillary mucinous neoplasms (IPMNs) relies on clinical and imaging features to select patients for either pancreatectomy or periodic image-based surveillance. We aimed to compare outcomes in patients with IPMNs who underwent surgery at diagnosis with those who underwent surgery after a period of surveillance and identify preoperative clinical and imaging features associated with advanced neoplasia. Methods: Patients with surgically resected IPMN (n = 450) were divided into 2 groups "immediate surgery" resection within 6 months of IPMN detection, and "surveillance surgery" resection after surveillance >6 months. Survival was analyzed with Kaplan-Meier estimates and Cox proportional hazard models. Results: Pancreatic cancers in the surveillance surgery group (n = 135) was more frequently stage I compared with the immediate surgery group (9/13, 69.2% vs 41/110, 37.3%; P = .027). Among Fukuoka "worrisome features," only main pancreatic duct dilation 5-9 mm (odds ratio [OR] = 3.12, 95% confidence interval [CI] 1.72-5.68; P < .001) and serum CA 19-9≥ 35 U/mL (OR = 2.82, 95% CI 1.31-6.06; P = .008) were significantly associated with advanced neoplasia. In addition, smoking history was associated with increased risk of advanced neoplasia (OR = 2.05, 95% CI 1.23-3.43). Occurrence of future cancer was 16-fold higher in IPMN with high-grade dysplasia when compared with low-grade dysplasia (hazard ratio 16.5; 95% CI 4.19-64.7). Conclusion: Surveillance-detected pancreatic cancers in patients with IPMNs are more frequently stage I, and IPMN-HGD on surgical pathology is associated with significant risk of future pancreatic cancer. In addition to known "high-risk" features, main pancreatic duct dilation 5-9 mm, CA 19-9 elevation, and smoking history are significantly associated with advanced neoplasia.