To determine the expression levels and distributional patterns of CCL17, CCL22 and E-cadherin using real-time PCR, Western blot, and immunohistochemistry within the ethmoid sinus mucosa of healthy controls and the polyp of patients with CRSwNP to evaluate the possible effects of CCL17 and CCL22 in the pathogenesis of NPs. The gene discussed is CCL17; the disease is polyp.