p53 and ki67 expression as prognostic factors for cancer-related survival in stage T1 transitional cell bladder carcinoma.

OBJECTIVE: To determine prognostic factors for survival in bladder transitional cell carcinoma (TCC), and the prognostic value of p53 and ki67.

MATERIAL AND METHODS: A study was made of patients with stage T1 primary bladder TCC (n = 175). The immunohistochemical study was carried out using DO7 and MIB-1 monoclonal antibodies, for p53 and ki67, respectively. Kaplan-Meier methodology was used for the survival analysis, and the log-rank test was applied in order to determine accumulated probability rates of survival. Moreover, Cox's multivariate regression analysis was also used to establish the variables associated with survival. Receiver operating characteristic (ROC) curves were also drawn, with the aim of determining the prognostic capacity of p53 and ki67.

RESULTS: The average follow-up period was 7.3 years. Cancer-related survival rates at 5 and 10 years were 89.51 and 80.68%, respectively. The increase in p53 and ki67 expressions paralleled the histological grade, both markers showing significant inter-group differences (P = 0.0000). The variables which modified cancer-related survival significantly in the univariate analysis were the following: tumour multifocality, solid microscopic morphology, large cell nucleus and a high expression of p53 and ki67. Independent cancer-related survival variables were: age, tumour size of >3 cm, a solid microscopic growth pattern and expression of p53.

CONCLUSIONS: The expression of p53, increase in age, tumour size of >3 cm and microscopic growth pattern are independent predictors for cancer-related survival. A positive correlation was observed, indicating that, the higher the expression of p53, the greater the probability of death.