The AUC of CEA was 0.697 (95% confidence interval: 0.637–0.758; p < 0.0001); CEA at a cutoff value of 5 ng/ml could discriminate CRC patients from HCs with a sensitivity of 32.7% and specificity of 95.2% (Figure 2A,B). This evidence concerns the gene CEACAM5 and colorectal carcinoma.