MedGen

A rare benign tumor composed entirely of neoplastic perineurial cells. It may occur in the soft tissues, intraneurally or in mucosal sites. [from NCI]

A usually exophytic mass attached to the underlying tissue by a broad base or a thin stalk. Polyps can be neoplastic or non-neoplastic. Neoplastic polyps usually represent proliferations of the epithelium, and are commonly seen in the gastrointestinal tract. Polyps of the gastrointestinal tract are often called adenomas, are associated with dysplasia, and may eventually transform into carcinomas. Non-neoplastic polyps may be inflammatory, degenerative, or the result of malformations. [from NCI]

A polypoid lesion that arises from the colon and protrudes into the lumen. This group includes adenomatous polyps, serrated polyps, and hamartomatous polyps. [from NCI]