A comparison between intraductal papillary neoplasms of the biliary tract (BT-IPMNs) and intraductal papillary mucinous neoplasms of the pancreas (P-IPMNs) reveals distinct clinical manifestations and outcomes

Background: Intraductal papillary mucinous neoplasm of the biliary tract (BT-IPMN) has been increasingly recognized as a biliary counterpart of intraductal papillary mucinous neoplasm of the pancreas (P-IPMN). However, there is limited information regarding whether BT-IPMNs and P-IPMNs behave in a similar fashion. Methods: We retrospectively compared clinicopathological variables between 9 patients with BT-IPMN and 44 patients with P-IPMN. Results: There was no significant difference in age between patients with BT-IPMN and those with P-IPMN. The male/female ratio was significantly higher in patients with P-IPMN than in those with BT-IPMN (P = 0.012). Clinical presentation with jaundice was more common in patients with BT-IPMN (67%) than in those with P-IPMN (4.5%, P = 0.002). In addition, serum levels of CEA and CA19-9 were higher in patients with BT-IPMN than in those with P-IPMN (P = 0.019 and P = 0.002, respectively). The pathological diagnosis of malignancy was significantly more common in patients with BT-IPMN (89%) than in those with P-IPMN (23%, P = 0.002). The association with invasive carcinoma was significantly more frequent in patients with BT-IPMN (44.4%) than in those with P-IPMN (6.8%, P = 0.008). Furthermore, survival time after surgical resection was significantly shorter in patients with BT-IPMN than in those with P-IPMN (P = 0.002). Conclusion: These findings reveal differences in clinicopathological features and prognosis between BT-IPMN and P-IPMN, thereby suggesting distinct biological pathways underlying the pathogenesis of these neoplasms.