Altered p53 and pRb expression is predictive of response to BCG treatment in T1G3 bladder cancer.

Background: The aim of this study was to determine the prognostic value of p53 and retinoblastoma protein (pRb) expression in patients with stage T1 grade 3 (T1G3) bladder cancer (BC) treated by transurethral resection of bladder tumour (TURBT) and intravesical instillations of bacillus Calmette-Guerin (BCG). Materials and Methods: p53 and pRb expression were independently recorded within a homogeneous series of 27 patients. Fisher exact test and the log-rank test were carried out, along with Kaplan-Meier survival analysis. Results: Sixteen tumours showed altered p53 expression, while 14 showed altered pRb expression. Overall, 7 tumours showed normal expression of both markers, 10 altered expression of one of the two markers, and 10 altered expression of both markers. Only altered pRb expression was an independent predictor of both recurrence (p=0.037) and progression (p=0.018); altered expression of both markers was a strong predictor (p=0.001) of progression. Conclusion: This is the first study demonstrating that altered p53 and pRb expression are predictive of T1G3 BC response to BCG treatment. These findings provide grounds for inclusion and prospective validation of these markers in the decision-making process for treating BC.