Recently, several studies have shown that CEA after preoperative chemoradiotherapy is associated with histologic response and prognosis in patients with rectal cancer.26, 27, 28 Those studies suggested that, when combined, pre‐ and post‐chemoradiotherapy CEA could be useful as prognostic factors for disease‐free survival in patients with rectal cancer who undergo treatment with neoadjuvant chemoradiotherapy and curative resection.26, 27, 28 Elevated CEA before preoperative therapy, as well as normalized CEA after preoperative therapy, may also have a specific prognostic impact. Here, CEACAM5 is linked to rectal cancer.