Objective: The most important predictive parameter for the biological behavior of urothelial carcinomas except depth of invasion is the histological grade of the tumor. However, crucial discordances arise between pathologists because of subjectivity in histological grading schemes and these discordances cause difficulties especially in lowgrade tumors. The number of studies aiming to predict the risk of recurrence and progression in urothelial carcinomas has therefore increased in recent years. Our aim in this study was to evaluate the relation of histopathological and clinical characteristics of urothelial carcinomas with proliferation and apoptosis markers and to determine predictive parameters for their biological behavior.

Material and Method: This study included 84 previously diagnosed cases of urothelial carcinoma of the urinary bladder. Immunohistochemical expressions of Ki-67, p53, Bcl-2, and Bax were examined in each case.

Results: Expressions of Ki-67 and p53 determined a significant relationship between pathological stage and histological grade of the cases. There was no significant relationship between the other apoptotic markers (Bcl-2, and Bax) and clinical or morphological parameters.

Conclusion: We concluded that the evaluation of Ki-67 and p53 expression combined with pathological stage and histological grade may give more accurate information about the biological behavior of urothelial carcinomas of the urinary bladder.