NLR, CEA and CA19-9 values showed statistically significant differences between BC and FA patients and the study revealed significantly higher diagnostic efficiency of combined indicators than of the single parameters: CEA (SN 81.8%, SP 69.4%, AUC = 0.799), NLR (SN 74.2%, SP 69.4%, AUC = 0.747), CA19-9 (SN 70.0%, SP 61.1%, AUC = 0.711). The gene discussed is CEACAM5; the disease is breast cancer.