Some other serum tumor markers, such as alpha-fetoprotein (AFP), carbohydrate antigen 125 (CA125), and carbohydrate antigen 153 (CA153) can also be elevated in CRC (Dolscheid-Pommerich et al., 2017; Huo et al., 2016; Ren et al., 2019). Here, AFP is linked to neoplasm.