CEACAM5 and colorectal carcinoma: Integrated analysis of targeted and untargeted serum metabolomics and faecal samples metagenome sequencing, a model based on 8 gut microbiome‐associated serum metabolites is identified to differentiate CRC patients and individuals with benign lesions as well as healthy individuals, which demonstrated a higher area under the curve (AUC) compared to traditional biomarker carcinoembryonic antigen (CEA).119