Adenoma

A neoplasm that arises from the glandular epithelium. It may be encapsulated or non-encapsulated. The neoplastic glandular epithelial cells may or may not display cellular atypia or dysplasia. Representative examples include gastrointestinal tract adenomas, thyroid gland follicular adenomas, and pituitary neuroendocrine tumors/adenomas. The vast majority are benign.

Source: NCI Thesaurus (C2855).