Topical and systemic steroids constitute the first choice in medical treatment for nasal polyps. Glucocorticoids sensitivity is significantly correlated with CST1 in nasal secretions. The goal of this randomized, double-blind, placebo-controlled clinical trial is to clarify the efficacy of a short course of CST1-guided oral glucocorticoids therapy for chronic rhinosinusitis with nasal polyps. Subjects were randomized to receive either oral glucocorticoids or oral placebo for 2 weeks. Endoscopic polyp score, Total Nasal Symptom Score(TNSS), SNOT-22 score, Cystatin 1 and other biomarkers were evaluated before and after the treatment. Researchers will compare oral glucocorticoids group and oral placebo group to test CST1 predictive model of glucocorticoid therapy for Chronic Rhinosinusitis with Polyps.