A Six-Week Course of Bacillus Calmette-Guérin Prophylaxis Is Insufficient to Prevent Tumor Recurrence in Nonmuscle Invasive Bladder Cancer with Strong-Positive Expression of p53

Abstract

Objective: To determine the impact of p53 overexpression on tumor recurrence after bacillus Calmette-Guérin (BCG) intravesical therapy in patients with nonmuscle invasive bladder cancer (NMIBC). Methods: Between January 1999 and December 2008, 275 patients who received six BCG intravesical instillations for NMIBC (transitional cell carcinoma) after transurethral resection were assessed for differences in outcomes according to the level of p53 overexpression. A multivariate logistic regression model was applied to assess the predictive capacity of variables for recurrence. Overexpression of p53 was determined using monoclonal p53-DO7 antibody. Results: In 275 subjects, the recurrence rate was higher based on the level of p53 expression (p = 0.019). Based on multivariate analysis, a strong-positive p53 >60% (p = 0.031) and tumor grade (p = 0.015) were significant predictors for recurrence. Patients with a strong-positive p53 >60% had a much lower 5-year biochemical recurrence-free survival rate than patients with p53 ≤60% (72.1 vs. 31.5%, p < 0.001). Conclusions: Strong overexpression of p53 was predictive of recurrence in patients with NMIBC undergoing intravesical BCG treatment. A 6-week induction course of BCG alone is not sufficient to prevent recurrence in patients with NMIBC with high p53 expression; additional prophylactic strategies are needed for these patients.