Following analysis of the association between the serum levels of the analyzed proteins and the tumor stage of CRC according to the TNM classification, the concentrations of ADAM15, as well as the classical tumor markers CEA and CRP, were the highest in stage IV CRC, but the difference was significant only for CEA (p = 0.049) and CRP (p = 0.013). This evidence concerns the gene CEACAM5 and neoplasm.