Besides, the C-index of the nomogram only consisting of the tumor-specific factors (serum carcinoembryonic antigen, carbohydrate antigen 19-9, tumor number) could be improved to 0.737 (95% CI 0.062–0.768) from 0.625 (95% CI 0.585–0.665) when the PRG was incorporated (p < 0.001). The gene discussed is CEACAM5; the disease is neoplasm.