Figure 1.

Histopathological characteristics of epithelial damage of nasal mucosa and thickening of the basement membrane was assessed in hematoxylin and eosin stained sections using the following staging system: (A) Stage 0, normal epithelium (arrow) and basement membrane; (B) stage 1, cilia loss (arrow) and basement membrane thickening; (C) stage 2, eroded epithelium (arrow), thickening basement membrane and intact basal layer; and (D) stage 3, complete erosion (arrow) of the epithelium and massive thickening of the basement membrane (magnification, ×400). (E) Percentage of NP and control specimens observed at each stage. The percentage of NP specimens exhibiting stage 3 epithelial damage indicative was significantly greater compared with the control group (P=0.005). The control group exhibited more intact epithelia or mild epithelial shedding (stage 0) compared with the NP group (P=0.030). NP, nasal polyposis.