Association of cyclooxygenase-2 expression with prognosis of stage T1 grade 3 bladder cancer.

Objectives: To determine whether the expression of cyclooxygenase-2 (COX-2) has prognostic significance in Stage T1G3 transitional cell carcinoma of the bladder, the most unfavorable subgroup in terms of recurrence and disease progression.

Methods: Thirty-seven consecutive patients with initial T1G3 transitional cell carcinoma, who had undergone complete transurethral resection, followed by 6 weeks of intravesical instillation of bacille Calmette-Guérin (BCG), and with at least 1 year of follow-up, were enrolled in the study. Paraffin-embedded cancer tissue samples were immunohistochemically stained for COX-2, and possible correlations with clinicopathologic features, such as age, shape and multiplicity of tumor, recurrence, and progression were examined.

Results: The median follow-up was 27 months (range 12 to 67). Sixteen patients (43.2%) experienced recurrence and 6 (16.2%) had progression defined as muscle invasion. Of 37 specimens, 16 (43.2%) stained positive for COX-2, defined as 5% or greater of positively stained cancer cells. COX-2 expression was statistically significant in predicting both recurrence (P = 0.0493) and disease progression (P = 0.0272). Patient age and the shape and multiplicity of tumors were not significantly predictive of recurrence or progression.

Conclusions: In a pathologically homogeneous group of T1G3 transitional cell carcinoma of the bladder, the expression of COX-2 correlated with recurrence and progression. Thus, patients with COX-2 positive superficial bladder cancer may need to be followed up more vigorously. Additional studies on the mechanistic implications of COX-2 with respect to recurrence and progression and the possible application of a COX-2 inhibitor to prevent recurrence and progression of superficial bladder cancer are warranted.