Ki67 and Bcl-2 immunoexpression in primitive urothelial bladder carcinoma

Bladder cancer ranks among eight human malignant lesions, 90% being urothelial carcinomas. We evaluated the Ki67 and Bcl-2 immunoexpression and their correlations with clinicopathological parameters. The study included 45 primitive bladder urothelial carcinoma diagnosed in patients aged in VI and VII decades of life, predominantly in males. Histopathologically, the most numerous were moderately differentiated carcinomas (68.8%), most patients being classified in stage I of disease (48.8%). The analysis for Ki67 immunostain revealed positivity in 71.1% of cases, with higher values in moderate and poorly differentiated tumors in stage III or IV of disease. In contrast, immunoreactivity for Bcl-2 was present in 33.3% of well and moderately differentiated analyzed tumors and classified in stage I and II of disease. Tumor stage and grade is not correlated with Bcl-2 but there was a strong correlation with Ki67 proliferation index. Ki67 immunoexpression may be helpful to identify patients at high risk who may benefit by adjuvant therapies.