Endoscopy versus double-contrast barium enema in the evaluation of patients with symptoms suggestive of colorectal carcinoma.

Two hundred seventy-six patients with positive findings on a stool guaiac test, hematochezia, a change in bowel habits, or a family history of colorectal carcinoma were referred to the colorectal clinic for further investigation. There were 105 men and 171 women. All patients underwent examination with the 65 cm flexible sigmoidoscope. Patients with no abnormalities on endoscopy underwent a double-contrast barium enema. If the barium enema revealed a polyp or other suspicious pathologic process, the patient was referred for colonoscopy. In 258 patients, findings of barium enema and flexible sigmoidoscopy were in agreement. The findings in 178 of these examinations were completely negative, and in the remaining 80 cases flexible endoscopy and barium enema revealed diverticulosis. In an additional 18 patients, negative findings on flexible sigmoidoscopy were followed by positive findings on barium enema. Thirteen of these 18 patients (72 percent) had negative findings on colonoscopies and therefore had false-positive findings on barium enema. In the remaining five patients (28 percent), an unsuspected colonic carcinoma or premalignant polyp was discovered on barium enema and documented by colonoscopy. Also, in four of these five patients, colonoscopy found additional polyps that were not seen on barium enema.