CEACAM5 and cancer: Preoperative FPR combined with CEA could effectively distinguish early-stage cancer from benign colorectal polyps, with an AUC, Sen, and Spe of 0.835, 68.30%, and 83.40% in the discovery cohort, 0.823, 61.90%, and 83.60% in the validation cohort, and 0.829, 63.20%, and 86.00% in the overall population, respectively.