The colorectal cancer group was older (66 vs. 38 years old), and the levels of NLR (2.15 vs. 1.69), D-D (139 vs. 58 ng/ml), CEA (4.90 vs. 1.57 ng/ml), and CD8+T (732 vs. 532 μL−1) were significantly higher than those in the control group, while the levels of CD3 + T (728 vs. 1332 μL−1), CD4+T (612 vs. 868 μL−1), CD4+/CD8+ ratio (1.34 vs. 1.53), and PNI (49.4 vs. 52.8) were significantly lower than those in the control group (P < 0.05). The gene discussed is CEACAM5; the disease is colorectal cancer.