Overexpression of COX-2 in oral squamous cell carcinoma patients undergoing chemoradiotherapy

AIMS AND OBJECTIVES: To evaluate the prognostic significance of cyclooxygenase-2 (COX-2) overexpression in oral squamous cell carcinoma (OSCC) patients undergoing chemoradiation therapy. Purpose of the study was to determine whether COX-2 could be used as a diagnostic and prognostic index in OSCC. MATERIALS AND METHODS: Forty-four patients of SCC were included in the present study and immunohistochemical examination was done for COX-2 expression. Negative and <5% COX-2 positivity were taken as negative expression and ≥5% COX-2 positivity as positive expression group. ≥30% COX-2 positivity was taken as overexpressed group and <30% COX-2 positivity was taken as underexpressed group. All the data were analyzed statistically. RESULTS: COX-2 overexpression in OSCC was found in 15.90% cases. The proportion of COX-2 overexpression was higher in patients with large tumor size than in those with small tumor size. The proportions of COX-2 positive expression cases were higher with cervical lymph node metastasis. Negative COX-2 expression was higher in well-differentiated OSCC and positive expression was higher in moderately differentiated tumors. COX-2 underexpressed cases had better response to chemoradiation therapy as compared to cases with overexpressed COX-2. CONCLUSION: COX-2 expression in OSCC can be used as a prognostic marker. Studies with large sample size and long-term follow-up are required to find out the exact role and prognostic significance of COX-2 expression in OSCC.