Concurrent presentation of an intraductal tubulopapillary neoplasm and intraductal papillary mucinous neoplasm in the branch duct of the pancreas, with a superior mesenteric artery aneurysm: a case report

BACKGROUND: Since the concept of intraductal tubulopapillary neoplasm (ITPN) was introduced in the current World Health Organization classification of tumors, the number of reports of ITPN occurrence has increased gradually. However, ITPN is usually located in the main pancreatic duct, with few reports of a branch duct ITPN. As a result, imaging protocols for the diagnosis of a branch duct ITPN have not been established. CASE PRESENTATION: We report a case of a concurrent presentation of a branch duct ITPN and intraductal papillary mucinous neoplasm (IPMN) in the head of the pancreas, with a superior mesenteric artery (SMA) aneurysm. Initially, the cystic masses in the pancreatic head were diagnosed as branch duct IPMNs, with treatment consisting of a pylorus-preserving pancreaticoduodenectomy, in combination with an aneurysmectomy performed for treatment of the SMA aneurysm. Pathological examination confirmed these cysts were a combination of branch-type ITPN and IPMN. The patient recovered from the treatment without complication, with no evidence of recurrence over a period of 34 months post-surgery. CONCLUSION: This case report of a synchronous presentation of an ITPN and IPMN indicates the difficulty in differentiating these two types of neoplasms in the branch duct of the pancreatic head.