CXCL12 and cancer: The presence of peritumoral lymphatic vessels accelerates LN metastasis in patients with head and neck cancer by accelerating lymphatic intravasation (72) and actively promotes cancer cell transport to LNs in preclinical models via chemoinvasion that utilizes chemokine signaling pathway such as CCR7 – CCL21 (87, 88), CXCR4 – CXCL12 (89), and CCL1-CCR8 (90) (Figure 1).