CEACAM5 and neoplasm: It is about the presence/absence of lymphovascular and/or perineural invasion of the tumor cells, high-grade tumor, the status of the resection margins (R0—tumor-free margins, R1—microscopically identified tumor invasion of the margins, R2—macroscopic evidence of margin infiltration), perforation, obstruction, number of examined lymph nodes and preoperative serum level of carcinoembryonic antigen (CEA).