Objective: To evaluate the effects of glucocorticoid on tissue remodeling of nasal mucosa from patients with chronic rhinosinusitis with nasal polyposis (CRSwNP) after endoscopic surgery.
Methods: Nasal mucosa obtained from 30 cases of CRSwNP during nasal endoscopic surgery were considered as preoperation group. These patients were equally divided into two groups after surgery, ie. glucocorticoid group and contrast group. Uncinate process mucosa samples from 6 patients during septoplasty were considered as normal control group. Epithelial damage and expressions of transforming growth factor-beta1 (TGF-beta1) and collagen III were studied by light microscopy and immunohistochemistry.
Results: In nasal mucosa samples of preoperation group, epithelial damage showed 90% (27/30) of stage 3 and 10% (3/30) of stage 2; TGF-beta1 positive cells and collagen III positive basement membrane with more than 20 microm were seen in 87% (26/30) and 97% (29/30) of samples, respectively. No significant difference was observed in morphology of nasal mucosa and expressions of TGF-beta1 and collagen III between glucocorticoid group and contrast group at 1th month after surgery. At 3th month after surgery, epithelial damage displayed 53% (8/15) of stage 3, 33% (5/15) of stage 2 and 14% (2/15) of stage 1 in contrast group; however, 93% (14/15) of stage 0 and 7% (1/15) of stage 1 in glucocorticoid group. The difference of epithelial damage between two groups was significant (Uc = 4.481, P < 0.05). The amount of TGF-beta1 positive cell was markedly higher in contrast group than in glucocorticoid group (t = 2.32, P < 0.05). The thickness of basement membrane was above 20 microm in 67% of contrast group (10 cases) and 27% of glucocorticoid group (4 cases); the difference between the two groups was significant (P < 0.05).
Conclusions: Tissue remodeling is present in nasal mucosa of CRSwNP after endoscopic surgery. Early and appropriate administration of glucocorticoid plays an important role in inhibition of tissue remodeling and prevention of relapse. Postoperative follow-up should not be less than 3 month.