Unexpected pancreatic mixed neuroendocrine-nonneuroendocrine neoplasms (MiNEN)-reflection on a case report.

The authors present a case involving a 51-year-old male who was diagnosed with a 4-cm mass in the body of the pancreas, initially suspected to be a ductal adenocarcinoma due to an elevated Ca 19.9 during routine analysis. Subsequent imaging studies confirmed a resectable disease without suspicious lymph nodes or distant metastasis, leading to the proposal of surgery. The patient underwent a laparoscopic distal splenopancreatectomy, which was uneventful. The histopathological examination revealed a 3.7-cm pancreatic mixed neuroendocrine neoplasia (MiNEN) with a predominant high-grade ductal adenocarcinoma component and a concurrent high-grade neuroendocrine carcinoma, with negative margins. Two lymph node metastases were identified, each representing metastasis of one of the components. The tumor was classified as pT2N1M0. Currently, the patient is undergoing chemotherapy with FOLFIRINOX. This case prompts reflection on the optimal treatment strategy for pancreatic MiNEN and raises the question of how the preoperative diagnosis could influence the patient's outcome.