To explore the role that hPGDS-PGD2-CRTH2 pathway plays in CRSwNP, especially in the recurrence of nasal polyps, we screened the expression of hPGDS-PGD2-CRTH2 in nasal polyps defined by their tendency to recur post-surgery. The gene discussed is HPGDS; the disease is chronic rhinosinusitis with nasal polyps.