[Traumatic Neuroma Mimicking Lymph Node Metastasis of Pancreatic Neuroendocrine Neoplasms Developed after Pancreatoduodenectomy-A Case Report].

A traumatic neuroma is a benign tumor consisting of a non-neoplastic growth of injured nerves as a result of trauma or surgery. It is rarely found in an abdominal cavity, but some reports showed that it occurred around the bile duct. We report a case of a 72-year-old man who underwent subtotal stomach-preserving pancreatoduodenectomy for pancreatic neuroendocrine neoplasms 4 years ago. An abdominal contrast-enhanced CT follow-up examination revealed a growing nodule on the dorsal surface of the portal vein. The lesion showed a mild increase in fluorodeoxyglucose uptake in FDG-PET⊘CT. A lymph node metastasis of pancreatic neuroendocrine neoplasms was suspected. Nodule resection was performed for purpose of diagnosis and treatment. The final pathological diagnosis was traumatic neuroma with no evidence of recurrence. Traumatic neuromas developed after pancreatoduodenectomy have not been reported. Postoperative masses around the bile ducts should also be considered traumatic neuromas.