Synchronous neuroendocrine tumors in both the pancreas and ileum: A case report

• This is the first case of synchronous pancreatic and ileal NET in a non-MEN 1 patient.
• Both morphologic and immunophenotypic findings were different.
• The synchronous occurrence of these tumors may be considered as a chance occurrence.

IntroductionAlthough it is well-known that in multiple endocrine neoplasia type 1 (MEN 1) disease, multiple endocrine lesions frequently occur, synchronous or metachronous neuroendocrine tumors (NETs) in non-MEN 1 patients are extremely rare.Presentation of caseAn asymptomatic 72-year-old woman with an ileal NET was referred to our hospital. Abdominal computed tomography revealed another circular tumor within the pancreatic head. She was classified as a non-MEN 1 patient. An operative procedure was performed with a preoperative diagnosis of synchronous NET, which was confirmed by pathological examination.DiscussionBoth morphologic and immunophenotypic findings were different between in the ileum and pancreas. Therefore, it was reasonable to consider that both tumors were primary tumors. The synchronous occurrence of these tumors is unusual, and it may be considered as a chance occurrence.ConclusionWe here report the first case of synchronous pancreatic NET and ileal NET in a non-MEN 1 patient.