An insulin-producing neuroendocrine tumor arising from the beta cells of the pancreas. It may or may not be associated with inappropriate secretion of insulin and an associated clinical syndrome. The disease is pancreatic insulin-producing neuroendocrine tumor (MONDO_0005048, a Monarch Disease Ontology identifier). Also known as: Beta cell tumor, Beta cell tumor of pancreas, Beta cell tumor of the pancreas, Beta cell tumour, Beta cell tumour of pancreas, Beta cell tumour of the pancreas, beta cell neoplasm, beta cell tumor of the pancreas.