<unk> s are believed to arise from various<unk>  cells whose normal function is to serve at the<unk>  interface.<unk>  cells are present not only in endocrine glands throughout the body that produce hormones, but are found in all body tissues.
Neuroendocrine tumor
Pituitary adenoma
Metastatic insulinoma
Insulinoma
Glucagonoma
Granular cell tumor
Endocrine gland neoplasm
Glial tumor