IL4 and nasal cavity polyp: Considering role of cytokines in the research on chronic rhinosinusitis and the Ki-67 appearance during cell proliferation and significant rates of nasal polyp recurrence, the aim of this work was to investigate the complex appearance, relative distribution, and interlinks of IL-1, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12, and Ki-67 in CRSwNP-affected human nasal mucosa in the case of recurrent nasal polyps after previous surgery.