Prognostic influence of coagulative tumor necrosis and the tumor location for T1a renal cell carcinoma

Abstract

Purpose: The presence of histologic coagulative necrosis in the primary tumors of patients with renal cell carcinoma has been suggested to be an important predictor of survival. This study aimed to evaluate the relationship of tumor necrosis and tumor location as compared to the other clinical features. Materials and methods: From June 1995 to April 2004 we retrospectively reviewed the records of 204 patients who underwent unilateral radical nephrectomy for stage T1a renal cell carcinoma. The presence of histologic coagulative necrosis in the primary tumors was recorded and the location of tumor was classified based on the computed tomography (CT) scan. Overall survival was estimated using the Kaplan-Meier method and the log-rank test, and the prognostic factors that influenced on survival were estimated using the Cox proportional hazard regression model. Results: In this study, radical nephrectomy was performed in 148 men and 56 women with a mean age of 54.9 years (age range: 23 to 77). The mean follow-up was 31.3 months (range: 6 to 106 months). The average size of the renal cell carcinoma was 3.0cm (range: 1 to 4). The tumor locations were categorized into 2 types according to the centrality and verticality. The incidence of necrosis in T1a renal cell carcinoma was 8.7% (n=18). On the analysis of the overall survival using the log rank test, tumor necrosis (p=0.01) was a statistically significant factor. Conclusions: For the patients with T1a renal cell carcinoma (2002 TNM stage), the presence of tumor necrosis was significantly associated with overall survival.