The early detection of colorectal cancer is key to the improvement of patient survival. Although fecal occult blood testing and carcinoembryonic antigen (CEA) in serum are widely used as non-invasive screening methods, they have limited sensitivity. Forty-five patients who underwent surgery for primary colorectal cancer were enrolled in this study. Sixteen (36%) were determined to have Stage I tumors, 15 (33%) Stage II tumors and 14 (31%) Stage III tumors. Serum samples from a non-colorectal

more »

... cer group of 22 patients with no tumors were analyzed as a control. In each serum sample, CEA, p53 antibodies and CEA-IgM complexes were measured. The combination of these three tests had an overall sensitivity of 53% (24/45), and revealed 31% (5/16) of the tumors to be in Stage I, 53% (8/15) to be in Stage II and 79% (11/14) to be in Stage III, while the false positive rate was 18% (4/22). The combined use of these three tests in serum is potentially an effective screening method for the detection of colorectal cancer, at even the early stages of the disease.