Comparative analysis of MiB1 and p53 expression in human bladder tumors and their correlation with cancer progression.

Expression of p53 and MiB1, markers of tumor proliferation, was evaluated in human bladder tumors, and correlated with ploidy and cancer progression in 83 consecutive patients. Transurethral resection ofa newly diagnosed bladder tumor was performed in 73 cases, and systematic bladder biopsies were performed in 10 cases after bacillus Calmette-Guerin (BCG) treatment. p53 and MiB1 expression were performed by an immunohistochemical technique and the ploidy was determined on a frozen fragment of the tumor. p53 expression was correlated in relation to grade, stage and combination of grade and stage. MiB1 expression was correlated with cytological grade, and a significant difference was demonstrated between pT0 and pTa, pTa and pT1, pTa and pT2 tumors but not between pT1 and greater than or equal to pT2 tumors. A discordance was observed for the comparison of p53 and MIBI values, stage by stage, suggesting that these two techniques are independent of each other. A larger proportion of aneuploid tumors were positive for p53 and MiB1 (64.8 vs. 86.5%, respectively), but p53 and MiB1 immunostaining were not better indicators than ploidy alone to predict cancer progression.