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) o f the bladder and its role as a predictor of response to treatment. Pa tients and methods Tumour samples from 30 patients (two women and 28 m en, mean age 60.1 years, range 44-75) with pTa/pT1 tumours were assess ed immunohistochemically using the Pab1801 monoclonal antibody and sta ndard avidin-biotin peroxidase staining for p53 protein. Results Tumou rs from six patients (20%) showed nuclear accumulation of p53; five of these patients failed intravesical therapy with bacille Calmette-Guer in (BCG) and progressed to muscle invasive and/or metastatic disease, in contrast to six of 24 patients with no detectable nuclear oncoprote in. Conclusions The nuclear accumulation of p53 appears to be a progno stic indicator of tumour unresponsive to intravesical treatment, even with the most potent agent (BCG). Therefore, early radical treatment m odalities must be seriously considered in this group of patients.