Non-functioning neuroendocrine pancreatic tumors transforming to malignant insulinomas - four cases and review of the literature.
OBJECTIVE: Neuroendocrine tumors of the pancreas (Pan-NETs) are rare, but among the most common neuroendocrine neoplasias. They are mostly slowly growing with a capacity to metastasize, but transition to a higher grade occurs, which lead to a more aggressive tumor phenotype. Very seldom, non-functional tumors can become hormona.....