Such features that have been associated with a worse prognosis in CRC patients are a T4 primary; high-grade/poorly differentiated histology; lymphovascular invasion; perineural invasion; clinical bowel obstruction or perforation; close, indeterminate, or positive margins; inadequately sampled lymph nodes; a high preoperative serum carcinoembryonic antigen (CEA) level; and high levels of tumour budding. This evidence concerns the gene CEACAM5 and colorectal carcinoma.