Some TIICs, such as neutrophils, cancer-associated fibroblasts (CAFs), memory CD4+ T cells, gamma delta T cells, resting natural killer (NK) cells, activated NK cells, M1 macrophages, myeloid dendritic cells, and mast cells, have been identified to correlate with the development and progression of various malignancies, especially CRC. This evidence concerns the gene CD4 and colorectal carcinoma.