Abstract: To explore the correlation between histopathological characteristics and mechanism of nasal polyps.　MethodsNasal polyps of each patient who underwent nasal endoscopic sinus surgery were stained with HE and Toluidine Blue to count the number of eosiophils, lymphocytes, mast cells, plasma cells and neutrophil cells under a light microscope and were divided into 4 groups according to their histopathological characteristics. The data of the 4 groups were analyzed with One-Way ANOVA.　ResultsEosinophils were found in 69(51.49%) nasal polyps, lymphocytes were found in 52(38.81%) nasal polyps, both of them were found in 10(7.46%) nasal polyps, and neutrophil cells were found in 3(2.24%) nasal polyps. Furthermore, the difference of the mean number of eosinophils among the 4 groups was significant (P＜0.05). The difference was also significant in lymphocyte number, mast cell number, plasma cell number and neutrophil cell number. The number of eosinophils and mast cells was negatively correlated(r＝－0.534，P＜0.01), while the number of lymphocytes and mast cells was positively correlated(r＝0.601，P＜0.01), and the number of plasma cells and mast cells was positively correlated(r＝0.202，P＜0.05). ConclusionsThe accumulation of eosinophils in the nasal polyps does not appear to be related to the presence of mast cells and allergy. The infiltration of inflammatory cells and their interaction may be important steps in the formation of nasal polyps. The histopathological classification of nasal polyps may be helpful for exploring the mechanisms of nasal polyps.

Key words: Eosinophil, Lymphocytes, Nasal polyps, Mast cells, Plasma cells