[Value of preoperative colonoscopy in colon-rectal neoplasms].

The surgical approach to treat colo-rectal carcinoma is usually based on the findings of barium enema. In 102 patients we reviewed the yield of pre-operative colonoscopy. Barium enema revealed the cancer in 76 of 84 patients (91%), whereas colonoscopy did so in 96 of 102 subjects (94%). In addition, 5 associated cancerous lesions were demonstrated by colonoscopy and none by barium enema. Associated benign lesions were seen in 14 patients. In 5 patients the surgical plan based on the barium enema was modified by the findings at colonoscopy. Eight false negatives to barium enema were correctly diagnosed by colonoscopy. We conclude that colonoscopy yields valuable information, beyond that of barium enema, in patients with colo-rectal cancer.