CEACAM5 and breast cancer: And the AUC of CEA, CA153, and FER for distinguishing patients with breast cancer and patients with benign breast diseases was 0.663 (95% CI: 0.625‐0.701), 0.613 (95% CI: 0.574‐0.652), and 0.615 (95% CI: 0.575‐0.655), respectively.