[PCNA and Ki-67 expression in locally confined renal adenocarcinoma. Relationship with various histopathologic variables and prognostic significance].

Objective: PCNA and Ki-67 expression are used as markers of cellular proliferation and different studies have investigated their value as prognostic indicators for renal adenocarcinoma. The aim of this study was to determine PCNA and Ki-67 expression in locally confined renal adenocarcinoma, their relationship with other histopathological variables and prognostic significance.

Methods: 58 cases of renal adenocarcinoma stages pT1-T3a N0 M0 (TNM 1997), treated by curative radical or partial nephrectomy were reviewed. The clinical and histopathological variables were analyzed. PCNA and Ki-67 expression in tissue embedded in paraffin were studied by immunohistochemical techniques.

Results: The mean percentage of nuclei that stained for PCNA was 7.03% (range 0-50%). Analysis of the correlation between PCNA and histopathological variables (size, grade and stage), showed a statistically significant correlation of PCNA only for the nuclear grade (p = 0.009). The mean percentage of nuclei that stained for Ki-67 expression was 2.96% (range 0-30%) and a relationship was found for size (p < 0.001), nuclear grade (p < 0.001) and stage (p < 0.001). The incidental clinical presentation, tumor size, stage, nuclear grade, PCNA and Ki-67 expression showed a relationship with survival. However, only perirenal fat infiltration, tumor size, nuclear grade and PCNA expression were found to be independent factors by multivariate analysis.

Conclusions: PCNA expression correlated with nuclear grade, while Ki-67 demonstrated a significant correlation with tumor size, grade and stage. Survival analysis showed a relationship of both markers with prognosis. However, only PCNA was found to be an independent factor by multivariate analysis.