Do synchronous adenomas influence prognosis after radical surgery for colorectal carcinoma? A prospective study.

From 1978 to 1983, radical surgery for colorectal cancer was performed in 319 consecutive patients who were included in a prospective evaluation of perioperative and repeated postoperative colonoscopy with polypectomy. Synchronous adenomas were found and removed in 87 patients. The probability of survival without recurrent cancer and of not dying from local and/or distant spread was significantly higher (p less than 0.02) in patients with synchronous adenomas than in those without. This unexpected finding could only to a minor degree be explained by a greater prevalence of well differentiated cancers and fewer poorly differentiated cancers in patients with synchronous adenomas. Detailed analysis revealed only one other major difference between the two groups, namely a higher risk of adenomas developing during follow-up of patients with synchronous adenomas (p less than 0.001). The present results may be relevant to future prospective clinical studies in which perioperative and regular postoperative colonoscopy is included.