Expression of cyclooxygenase-2 in patients with primary liver cancer and correlation with clinicopathological features

Objective: To study the expression of cyclooxygenase-2 (COX-2) in patients with primary liver cancer (PLC) and to correlate COX-2 expression with clinicopathological features. Methods: A total of 146 PLC tissue samples and 25 adjacent tissue samples, from patients who were diagnosed in our hospital between February 2014 and June 2016, were randomly selected for this study. COX-2 expression was detected in these samples using immunohistochemistry, and the correlation between COX-2 expression and clinicopathological features was explored. Results: The positive expression rate of COX-2 in PLC tissues was 57.53% (84/146), whereas COX-2 was not expressed in normal adjacent tissues. The difference in COX-2 expression between the two groups was significant (P<0.05). The expression level of COX-2 was correlated with the degree of tissue differentiation in patients (P<0.05), but was not associated with gender, age, history of hepatitis, cirrhosis, alpha-fetoprotein expression, aspartate aminotransferase expression, γ glutamyl transpeptidase expression, alkaline phosphatase expression, tumor size, or American Joint Cancer Committee (AJCC) stage (P>0.05). The 3-year survival rate for patients with positive COX-2 expression was 35.71% (30/84), which was significantly shorter than that for patients with negative COX-2 expression, which was 79.03% (49/62) (P<0.05). According to a multivariate analysis, tissue differentiation and COX-2 protein expression levels can be used as independent risk factors in PLC patients. Conclusion: COX-2 is highly expressed in PLC tissues, and its expression level is related to the degree of tissue differentiation. COX-2 can be used as an independent risk factor and an effective indicator for evaluating the prognosis of PLC patients, providing new targets for the diagnosis and treatment of PLC.