RESUMO
PURPOSE: To identify new effective prognostic indicators for patients with nasopharyngeal carcinoma (NPC). METHODS: The immunohistochemical staining method was used to detect cyclooxygenase-2 (COX-2) protein in tumor tissues of 100 patients before and after chemoradiation. All the patients had stage III poorly differentiated NPC. RESULTS: The positive expression of COX-2 was decreased before and after chemotherapy. The expression levels of COX-2 in patients before treatment was associated with T stage (p<0.05). The changes in the positive expression of COX-2 following treatment was also associated with T stage (p<0.05). The clinical response rate (CR+PR) exhibited significant differences (p<0.05) in patients with negative, weakly positive, partially positive, and strongly positive COX-2 expression before treatment. The clinical response rate (CR+PR) exhibited significant differences (p<0.05) compared with the patients who were negative or weakly positive. The COX-2 positive expression level of patients with NPC before treatment was closely associated with the survival time and survival rate of the patients (p<0.05). The changes of COX-2 positive expression were associated with the survival time and survival rate (p<0.05) in patients with NPC following treatment. T stage, COX-2 expression before treatment and changes in COX-2 expression after treatment were independent factors affecting NPC prognosis (p<0.05). CONCLUSION: Changes in COX-2 expression levels before and after treatment may be a useful indicator for assessing the prognosis of NPC after chemoradiotherapy.
