Cyclo-oxygenase-2 Expression Is Associated With Lymph Node Metastasis in Oropharyngeal Squamous Cell Carcinoma Under the New TNM Classification.

BACKGROUND: This study aimed to investigate p16 and COX2 expression in oropharyngeal squamous cell carcinoma (OPSCC), and evaluate the prognostic role of COX2 expression under the new TNM classification. MATERIALS AND METHODS: Biopsy specimens obtained from 75 patients with OPSCC were stained for p16 and COX2 expression immunohistochemically. The results and clinical records were analyzed retrospectively. RESULTS: Fifty-nine patients (79%) were positive for p16. COX2 expression was correlated with poor relapse-free survival in patients overall, and in p16-positive patients. Smoking was positively associated with COX2 expression. Moreover, both positive COX2 expression and anterior wall tumor subsite were independently correlated with lymph node metastasis, which was the only independent prognostic factor in p16-positive OPSCC. CONCLUSION: The p16-positive rate in this study was comparable with that in the USA and Europe, and higher than that in other Asian countries. COX2 expression might affect the prognosis of p16-positive OPSCC through promoting lymph node metastasis.