The following variables were retrospectively reviewed in the electronic medical records: age, sex, body mass index (BMI), American Society of Anesthesiologists (ASA) classification for the assessment of patient comorbidities, preoperative CEA level, neoadjuvant and adjuvant chemotherapy, location (right, left, and rectum), pathologic tumor size (cm), tumor histology, TNM staging, lymphovascular invasion, perineural invasion, microsatellite instability (MSI), and the surgical outcomes mentioned above. The gene discussed is CEACAM5; the disease is neoplasm.