The value of a barium enema in the investigation of patients with rectal carcinoma.

A review of 545 patients with clinically diagnosed rectal carcinoma was conducted to determine the diagnostic usefulness of pre-operative barium enema and the frequency with which it was employed. Only 118 patients underwent pre-operative barium enema (21.7%). This successfully outlined the whole colon in 107 (90%). Synchronous carcinomas were detected in 9.3% of patients who underwent complete barium enema, compared to 4.3% of those who underwent laparotomy alone (P less than 0.05). Polyps were found in 23.4% of patients who had a barium enema but in only 14.7% of those who did not (P less than 0.05). Twenty-nine per cent of synchronous carcinomas and 11% of polyps were proximal to the descending colon and would have been beyond the reach of a flexible sigmoidoscope. Barium enema remains a useful investigation in patients with rectal carcinoma. It will outline the whole colon in most cases and will result in the detection of more synchronous carcinomas and polyps than if the surgeon relies on operative palpation alone.