PTGS2 and gallbladder carcinoma: The aims of the present study were to evaluate the tissue expression of the proteinsP53, E-CD, COX-2 and EGFR in tumor tissue and correlate these withclinical-epidemiological factors, and to evaluate their impact on the survival ofpatients with a diagnosis of gallbladder carcinoma, who underwent surgical resection ata tertiary-level referral center for cancer treatment.