This study aimed to explore: (i) which of serum TEs is correlated with the KRAS mutations or MSI status in patients with CRC, (ii) what kind of interactions is between the TEs associated with KRAS mutations or MSI status and certain demographic and clinical characteristics, and (iii) how do they interact with other TEs in patients with KRAS-positive CRC or MSI CRC. This evidence concerns the gene KRAS and colorectal carcinoma.