Nuclear Accumulation of Mutant P53 Protein: a Possible Predictor of Failure of Intravesical Therapy in Bladder Cancer

Objective: To investigate the expression and importance of the nuclear accumulation of p53 in superficial transitional cell carcinoma (TCC) of the bladder and its role as a predictor of response to treatment.

Patients And Methods: Tumour samples from 30 patients (two women and 28 men, mean age 60.1 years, range 44-75) with pTa/pT1 tumours were assessed immunohistochemically using the Pab1801 monoclonal antibody and standard avidin-biotin peroxidase staining for p53 protein.

Results: Tumours from six patients (20%) showed nuclear accumulation of p53; five of these patients failed intravesical therapy with bacille Calmette-Guèrin (BCG) and progressed to muscle invasive and/or metastatic disease, in contrast to six of 24 patients with no detectable nuclear oncoprotein.

Conclusions: The nuclear accumulation of p53 appears to be a prognostic indicator of tumour unresponsive to intravesical treatment, even with the most potent agent (BCG). Therefore, early radical treatment modalities must be seriously considered in this group of patients.