PTGS2 and laryngeal carcinoma: The pooled results suggested that COX-2 overexpression was significantly associated with the risk of laryngeal cancer (COX-2 positive in laryngeal cancer vs. COX-2 positive in normal control: 64.87% vs. 22.09%; OR = 11.62, 95% CI: 6.96–19.40, P < 0.05).