The polyp in the patient's colon was not pedunculated; the pathologist described it as flat and:

The polyp is described as sessile. Pedunculated polyps have a stalk (peduncle). Sessile polyps are flat and do not have a stalk and usually grows on the colonic mucosa. These kinds of polyps have increased risk for malignant transformation. Colonic polyps may be visualized by colonoscopy or sigmoidoscopy and multiple biopsies may be taken for histologic diagnosis (i.e. whether benign or malignant).