Objectives: It is known that intraductal papillary mucinous neoplasm (IPMN) is associated with a high incidence of extrapancreatic neoplasms. We tried to uncover the characteristics and gene expressions of IPMNs that coexist with other extrapancreatic gastrointestinal cancers.
Methods: We retrieved the surgical specimens from 54 IPMN patients, including 7 cases of IPMNs that coexisted with extrapancreatic gastrointestinal cancers. The immunohistochemical staining (p21, Bcl-2, p53, intestinal-type secretory mucin [MUC2], and MUC5AC) and the pathological subtypes of the tumor papillae (the intestinal type, pancreaticobiliary type, null type, or unclassified type) were analyzed.
Results: MUC2 expression was noticed more frequently in the IPMN coexisting with extrapancreatic cancers (6/7) than in the IPMN without extrapancreatic cancers (18/47; P = 0.04). There were no differences in p21 (P = 0.12), p53 (P = 0.25), and MUC5AC (P = 1.0) expressions between the 2 groups. IPMN with extrapancreatic cancers was noticed in all subtypes of papillae.
Conclusions: Regardless of the subtypes of papillae, transcription of the MUC2 might be related with the synchronous extrapancreatic gastrointestinal cancer development that is seen with IPMN. Therefore, careful systemic surveillance is needed to detect coexisting gastrointestinal cancer for all the subtypes of IPMN with MUC2 expression.