Rani et el have shown that in advanced CKD patients (stages G4 and G5) without tumor the levels of carcinoembryonic antigen (CEA), human chorionic gonadotropin (HCG), carbohydrate antigen 199 (CA199) and carbohydrate antigen 153 (CA153) were significantly higher compared to the healthy controls (Rani et al., 2019). Here, CEACAM5 is linked to neoplasm.