Since elevated levels of Th2 cell marker IL-5 were found to be associated with CRS occurrence and development in previous studies, this result further supports that CRS is linked to inflammatory response processes involving Th2 cells.20, 21 Finally, we investigated the expression levels of these 7 genes among different subtypes of CRSwNP. This evidence concerns the gene IL5 and chronic rhinosinusitis with nasal polyps.