High incidence of extrapancreatic neoplasms in patients with intraductal papillary mucinous neoplasms

Background: Intraductal papillary mucinous neoplasms (IPMNs) are associated with a high incidence of extrapancreatic neoplasms. Design: Retrospective study. Setting: Tertiary care referral center. Patients: Sixty-one patients underwent surgical resection for IPMN between January 1, 1993, and June 30, 2004. Thirty-eight patients with mucinous cystic neoplasms and 50 patients with pancreatic ductal adenocarcinoma also were examined for development of extrapancreatic neoplasms. Main Outcome Measures: The incidence and clinicopathological features of extrapancreatic neoplasms with IPMNs were compared with those with mucinous cystic neoplasm and pancreatic ductal adenocarcinoma. Results: Of the 61 patients with IPMNs, 24 (39%) developed 26 extrapancreatic neoplasms, and 18 (30%) had extrapancreatic malignancies. Gastric adenocarcinoma (33%) and colorectal adenocarcinoma (17%) were the most common neoplasms in the 24 patients. During postoperative follow-up, 3 patients died of malignant IPMNs, 3 of associated malignancies, and 1 of a nonmalignancy-related cause. Comparisons of the clinicopathological features in patients with IPMNs with and without associated malignancies revealed no significant differences in age, sex, family history of malignancy, history of cigarette smoking or alcohol abuse, or type of IPMN. The incidence of extrapancreatic neoplasms in patients with IPMN was significantly higher than in those with other pancreatic diseases such as mucinous cystic neoplasm (8%) or pancreatic ductal adenocarcinoma (10%). Conclusions: Frequently, IPMNs are associated with the development of extrapancreatic neoplasms. Considerable attention should be paid to the possible occurrence of other associated malignancies in patients with IPMNs, either concurrently or postoperatively. Further molecular studies may be necessary to elucidate the unusual association between IPMN and other primary neoplasms.