CEACAM5 and neoplasm: The methods currently used for PC diagnosis mainly concern imaging (computed tomography, magnetic resonance imaging, endoscopic ultrasound, and others), serological tests (carbohydrate antigen 19-9, carcinoembryonic antigen, carbohydrate antigen 125, carbohydrate antigen 242, macrophage inhibitory cytokine-1, mucin 5AC), liquid biopsies (circulating tumor DNA, circulating tumor cells, exosomes, microRNAs) [39].