Correlation of cyclooxygenase-2 expression and microvessel density with prognosis in transitional cell carcinoma of the upper urinary tract

Purpose: The aim of this study was to investigate the relationship of cyclooxygenase (COX)-2 expression and microvessel density (MVD), a reflection of angiogenesis, with prognosis in patients with transitional cell carcinoma of the upper urinary tract (TCC-UUT). Materials and Methods: Formalin-fixed, paraffin-embedded tissue sections of TCC-UUT from 91 patients, who had undergone radical nephroureterectomy, were examined immunohistochemically using antibodies against COX-2 and CD34. MVD was determined with CD34-stained slides. The expression patterns of COX-2 and MVD were compared with the clinicopathological variables. Results: The COX-2 expression was significantly correlated with T stage (p=0.002), N stage (p=0.010), and grade (p=0.027). MVD was also significantly correlated with T stage (p < 0.001), N stage (p=0.002), and grade (p=0.001). The COX-2 expression was significantly correlated with MVD (p=0.001). The survival rate of patients with COX-2 positive tumors or high MVD was significantly lower than that of patients with COX-2 negative tumors or low MVD, respectively (p=0.0013, p=0.0312). Univariate analyses identified T stage, N stage, grade, COX-2 expression, and MVD as significant prognostic factors for cancer-specific survival; multivariate analyses indicated that T stage was the only independent prognostic factor. Conclusions: The increased expression of COX-2 and MVD is associated with a worse prognosis in TCC-UUT. The COX-2 expression is correlated with MVD. These results suggest that COX-2 may play an important role in the progression of TCC-UUT and angiogenesis may be affected by COX-2 during the progression of TCC-UUT.