For instance, CRC has been classified as a function of the activated oncogenes (e.g., KRAS-positive versus KRAS-negative CRC) [3], as a function of the immune infiltrates (the immunoscore reflecting the density of CD3+ and CD8+ T cells) [4, 5] or as a function of microsatellite instability (MSI) resulting from DNA mismatch repair (MMR) defects [6]. Here, CD8A is linked to colorectal carcinoma.