Non-functioning neuroendocrine tumor of pancreas

A rare neuroendocrine tumor of pancreas characterized by a well-differentiated epithelial pancreatic neuroendocrine neoplasm measuring at least 0.5 cm, without distinct hormonal syndrome. Tumors <0.5 cm are called microadenomas. Microadenomatosis is the multifocal occurrence of microadenomas. Histopathologic examination shows an organoid growth pattern and expression of synaptophysin and chromogranin A on immunohistochemistry. Tumors are often discovered incidentally, or patients may present with symptoms related to local or metastatic tumor spread. Microadenomas are considered benign, while larger tumors may behave in a malignant manner with extrapancreatic spread, metastasis, or recurrence.