The prognostic value of KI-67, E-cadherin, P53 immunostaining in renal cell carcinoma (RCC)

Objectives This retrospective study was designed to assess the prognostic significance of some new biological markers such as Ki-67 antigen (related to proliferation rates), overexpression of p53 and E-cadherin (related to intercellular adhesion) in RCC: these markers have been compared to the clinical prognostic factors, stage and grade, to survival and to disease-free interval. Materials and methods Files from 95 patients (70 males, 25 females, median age 62 years) undergone to radical or partial nephrectomy from 1991 to 1994 were reviewed. Stage (according to TNM, 1992) and grade (according to Fuhrmann) were reassessed by a single pathologist; clinical progression, diseasefree interval and deaths were recorded. Sections from paraffin embebbed blocks of tissue were deparaffinized and immunostained for Ki-67 antigen, p53 and Ecadherin. The median value of the percentage of marked cells for Ki-67 ( 1%) was used as cut-off. For E-cadherin the presence or absence of immunostaining was regarded as cut-off. These biological factors, as well as the clinical ones, had been compared to survival and disease-free interval. Biological markers were then correlated to clinical ones. Statistical analysis, performed with the SPSS for Windows software, was done with the x , log-rank and Wilcoxon tests. A p value of .05 was considered significative. Multivariate analysis was performed using the Cox 's proporzional hazards model. Results Median follow-up was 33 months. Significative correlations were observed between grade, stage, and Ki-67 immunostaining at univariate analysis vs survival and disease-free interval. E-cadherin and p53 expressions were not correlated to survival nor to disease-free interval .Stage, grade and Ki67 confirmed their significance also at multivariate analysis. Correlation between clinical and biological factors was significative for Ki-67 and NMD both vs grade. Conclusions Our results confirm that clinical factors, stage and grade, are strongly predictive for the outcome of RCC, while among biological markers only Ki-67 seems to be related to outlook. Our data also confirm the unreliability of p53 and E-cadherin to predict outlook.