CXCR1 and neoplasm: The percentage of elevated concentrations (diagnostic sensitivity) of CXCL1 (57%) and CXCR1 (61%) was higher than that of the classical tumor marker CEA (46%), but lower than that of CRP (76%), whereas it increased in the combined analysis of CXCL1 and CXCR1 with CEA or CRP (Figure 2).