Acute pancreatitis in intraductal papillary mucinous neoplasms: A common predictor of malignant intestinal subtype.

BACKGROUND: Acute pancreatitis (AP) is a common presenting symptom of intraductal papillary mucinous neoplasms (IPMN). Our objective was to evaluate the clinical and pathologic features of IPMN that present with AP. We hypothesized that the intestinal epithelial subtype, which produces a highly viscous mucin containing MUC2 glycoprotein, is associated with the development of AP.

METHODS: We performed a case-control study, evaluating 325 patients with IPMN resected at our institution. Clinicopathologic features were assessed for patients with and without a history of AP and compared between the 2 groups.

RESULTS: A history of AP was found in 69 patients (21%). Of those, 33 (48%) experienced a single episode, and some patients had as many as 10 distinct attacks. Three patients presented with necrotizing pancreatitis requiring operative debridement. After resection, recurrent AP occurred in only 14%. A history of AP was associated with younger age (61 vs 70, P < .001), main duct involvement (odds ratio [OR] 1.73, 95% confidence interval [95% CI] 1.00-3.01; P = .049), intestinal subtype (OR 4.84, 95% CI 2.71-8.67; P < .001), and high-grade dysplasia (OR 1.82, 95% CI 1.07-3.11; P = .028). On multivariate analysis, AP was an independent predictor of intestinal subtype (OR 4.69, 95% CI 2.48-8.84, P < .001), malignancy (OR 1.97, 95% CI 1.07-3.63, P = .029), and main duct involvement (OR 1.87, 95% CI 1.02-3.43, P = .044).

CONCLUSION: AP is a frequent presenting symptom of IPMN. These patients are younger and have greater odds of harboring malignant intestinal-type IPMN involving the main pancreatic duct.