Cyclooxygenase-2 expression in advanced oral squamous cell carcinoma: a biomarker of poor prognosis

The primary aim of this study was to evaluate the impact of cyclooxygenase-2 (COX-2) expression on overall survival (OS), local recurrence-free survival (LRFS), and regional recurrence-free survival (RRFS) in patients diagnosed with advanced oral squamous cell carcinoma (AOSCC).

COX-2 expression levels were assessed in 191 cases of AOSCC and 50 cases of normal mucosa using immunohistochemistry (IHC). Comparisons were made between COX-2 expression in AOSCC and normal mucosal tissues, as well as its influence on OS, LRFS, and RRFS. The Cancer Genome Atlas (TCGA)- Head and Neck Squamous Cell Carcinoma (HNSC) database was utilized for validation.

In this cohort of 191 patients with AOSCC followed for 1-145 months (median: 68.3 months), AOSCC Patients exhibited significantly higher COX-2 expression compared to normal oral mucosa tissues. Consistent result was obtained from analysis of the AOSCC subgroup from TCGA HNSC cohort. In the subset of AOSCC patients filtered from the TCGA-HNSC database, COX-2 mRNA expression showed no statistically significant association with survival. However, In our cohort of AOSCC patients from IHC analysis, COX-2 expression emerged as an independent prognostic factor for OS, LRFS, and RRFS. Positive COX-2 expression was associated with a markedly increased risk of recurrence and diminished survival outcomes.

COX-2 is overexpressed in AOSCC and appears to be a potential adverse prognostic factor in our cohort. As a biomarker, COX-2 may offer valuable prognostic insights for AOSCC.