Internal Medicine

0521779407-C03 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 20:54

Colon Polyps and Tumors 369

➣all patients with adenomas found at sigmoidoscopy should

undergo colonoscopy

➣patients with only hyperplastic polyps have similar risk of prox-

imal advanced neoplasia as patients with no polyps and do not

need complete colon exam

■Positive Barium Enema or Virtual CT Colography

➣colonoscopy should be performed if polyps are found on imaging

studies

specific therapy

■most polyps can be removed at time of colonoscopy

■large polyps greater than 2 or 3 cm may require surgical resection

■pedunculated polyps with cancer localized to mucosa can be

resected with polypectomy if the margin is clear of tumor

■most flat or sessile polyps with cancer must be surgically removed

to confirm complete removal

follow-up

■all removed polyps should be examined; follow-up is based on

histology:

➣hyperplastic polyps: no specific follow-up needed

➣1 or 2 tubular adenomas <1 cm: low-risk lesion; surveillance

colonoscopy recommended at 5 years or more; emerging data

from the National Polyp Study may lead to extension of this inter-

val

➣advanced neoplasia defined as 3 or more adenomas, tubular

adenoma >1 cm, villous adenoma, adenoma with high-grade

dysplasia: follow-up at 3 years with colonoscopy; if the baseline

exam was incomplete, the exam should be repeated at 1 year; if

there was any doubt about complete removal of polyps, the exam

should be repeated in 6–12 months

complications and prognosis

Risks of Colonoscopy

■serious bleeding: 1–2/1,000 procedures, most associated with

polypectomy

■perforation: 1/1,000 procedures, most associated with polypectomy

■death: 1/10,000 associated with either perforation or bleeding

■cardiopulmonary complications: serious complications rare, but

transient hypoxia, hypotension, vagal reactions can occur during

colonoscopy