CD4 and colorectal carcinoma: As the tumor size increases, the presence of CD4+ CCR6+ CCR5+ CXCR3− and CD4+ CCR6+ CCR5− CXCR3− T cells also increase, which means that Th17/Th1 and Th17 cells’ presence is directly correlated with the size of the tumor in CRC liver metastasis.