In the US, the cumulative lifetime risk of developing
carcinoma of the upper gastrointestinal tract is less than 1 per cent, premalignant conditions are uncommon, and esophageal and gastric
malignancies are rarely curable even when identified early. Endoscopic screening of the upper gastrointestinal tract in asymptomatic persons thus cannot be justified. Surveillance of persons with certain uncommon conditions associated with a higher risk of upper
gastrointestinal cancer may be of benefit. These conditions include
achalasia,
Barrett's esophagus, chronic
atrophic gastritis with intestinal
metaplasia,
familial polyposis coli, gastric
polyps,
lye stricture,
Plummer-Vinson syndrome, and
tylosis. In the lower gastrointestinal tract, however, the lifetime risk of developing
carcinoma is 5 per cent, premalignant conditions and lesions are common, and
carcinoma is curable when detected at an early stage. Sigmoidoscopic screening of asymptomatic adults has been advocated by the American Cancer Society but has not become widely practiced because of its cost, required physician effort, low overall yield, and poor patient compliance. Surveillance by flexible sigmoidoscopy is recommended for persons at slightly increased risk of
colorectal carcinoma who have prior breast or gynecologic
malignancy or a family history of colorectal
malignancy. Colonoscopic surveillance is recommended for patients with high risk of
colorectal cancer who have had prior
colorectal carcinoma or
adenoma or who have
inflammatory bowel disease or a ureterosigmoidostomy.