Objective To study the relationship of CEA in the aged who had normal colonic mucosa,colonic polyps,or colonic cancer.Methods Serum CEA was measured in 25 aged persons with normal colonic mucosa,41 patients with colonic polyps and 39 patients with colonic cancer.Results Subjects with colonic cancer had higher CEA serum levels than those with polyps or normal mucosa,and the levels at the Dukes D stage were different from those in stages A,B and C.Conclusion CEA measurement is of supplementary value in the diagnosis,especially in the treatment and prognosis of colonic cancer.