Benign polyps can vary in size and appearance. These features can often predict the underlying pathology (e.g., adenomatous, hyperplastic, serrated, and inflammatory). Here, a small sessile polyp is seen. Sessile refers to the polyp “sitting” directly on the mucosa without a stalk. This is the most frequent appearance encountered when finding a polyp. Size can be difficult to determine for less experienced endoscopists, and estimation of size is variable by different endoscopists. This polyp is estimated to be about 4 mm in size.
The color of polyps may be similar to that of the surrounding mucosa, as seen here, making detection difficult in some instances.
Polyps may sit on top of haustral folds, as seen here, or may arise on the flat portion of the colon wall.
As polyps grow in size, they may remain sessile, sitting directly on the colonic wall.
Some polyps, regardless of size, may develop a short, nearly undetectable stalk beneath them, as seen here. This is regarded as being semi-pedunculated.
The short stalk in this semi-pendunculated polyp is not readily visible. However, its semi-pedunculated nature was evident by the mobility of the polyp, “flopping” onto both sides of the haustral fold as the endoscopist later moved it with a polypectomy snare.
In this case, the larger sized polyp had a short stalk, allowing it to attach to the back of the haustral fold.
While the polyp stalk is usually evident by its thinner diameter compared to the head of the polyp, it occasionally may be the same size as the head of the polyp. Here, the stalk is easily distinguishable from the head of the polyp, not by size, but by color of the stalk (pale) compared to the erythematous head of the polyp. It is the head of the polyp that contains the adenomatous tissue.