Mixed neuroendocrine–nonneuroendocrine neoplasms of duodenum and the ampulla of Vater: A case report

Mixed neuroendocrine–nonneuroendocrine neoplasms (MiNEN) are rare neoplasms. Comprising of two distinct entities, a neuroendocrine and a nonneuroendocrine component, usually an adenocarcinoma, they are highly aggressive neoplasms with a poor prognosis. We report the case of a 62-year-old Caucasian woman with duodenal and ampullary MiNEN. A computed tomography scan unveiled a neoplastic lesion involving the ampulla of Vater. Subsequently, the patient underwent a surgical intervention (modified Whipple procedure) with an initial diagnosis of adenocarcinoma of the ampulla of Vater and the head of the pancreas. After resection, histological examination revealed MiNEN, originating from the duodenum and ampulla of Vater with the presence of an adenocarcinoma and a neuroendocrine tumor (NET G2). The final histological staging was pT4N2. The primary objective of this case report, which presents a duodenal ampullary MiNEN, is to contribute to the management of this rare disease through a detailed literature review.