IL9 and chronic rhinosinusitis with nasal polyps: Biomarkers found to differentiate CRS phenotypes included IL-4, IL-5, IL-9, IL-13, C-C motif chemokine ligand 2 (CCL2), CCL3, C-X-C motif chemokine ligand 11 (CXCL11), and IgE which were increased in CRSwNP compared to CRSsNP, while the reverse was true for IL-2, IL-8, and vascular endothelial growth factor A (VEGF-A).