Predictive value of p53 and pRb immunostaining in locally advanced bladder cancer treated with cystectomy

We elucidate the association between altered immunostaining for retinoblastoma gene protein (pRb) and p53 nuclear proteins, and cancer specific death in patients treated with cystectomy for locally advanced bladder cancer.

The hospital records of 173 patients treated with cystectomy for advanced urothelial bladder cancer between 1967 and 1992 were retrospectively reviewed. Representative biopsies obtained before treatment were sectioned and stained using the standard immunohistochemical technique with antibody DO-7 (p53) and antibody PMG3-245 (pRb). A tumor was considered to have an altered p53 expression if 20% or more of tumor cells exhibited nuclear staining. Similarly, if no tumor cell had nuclear immunostaining the tumor was considered to have an altered pRb expression.

An altered expression was observed for p53 in 98 tumors (57%) and for pRb in 60 (35%). In a proportional hazards analysis no association was found between an altered expression of pRb or p53 and cancer specific death. This finding was also true in another analysis when the results of immunostaining for pRb and p53 were combined.

An altered expression for pRb and/or p53 was not correlated to cancer specific death. Thus, these parameters could not be used as predictors of treatment outcome after cystectomy for locally advanced bladder cancer.