The objective of this study was to investigate well known risk factors of a renal cell carcinoma (RCC) and the Charlson-comorbidity-index on a possible influence on the postoperative overall survival (OS) of patients suffering from RCC. For this reason, patient- and health-related parameters of 152 patients, which were contracted and surgically treated for RCC between 1995-2005 at the Charité Universitätsmedizin Berlin, Campus Benjamin Franklin, Department of Urology, have been investigated. The parameters pertaining to smoking, intake of analgesics, intake of diuretics, blood pressure, renal function, obesity and the Charlson-comorbidity-index with respect to the postoperative OS were reviewed retrospectively and analyzed employing univariate and multivariate analysis. In the univariate analysis both, smoking and intake of diuretics, showed a significant influence on the postoperative OS. With a median survival of 115 month compared to non-smokers with 144 month, smokers showed a nearly 2,5 years reduced median survival. Similar results could be shown for intake of diuretics with a median survival of 113 month compared to the group without intake of diuretics with 142 month and a nearly 2,5 year reduced median survival. No significant correlation to reduced postoperative OS could be demonstrated for patients with/without permanent intake of analgesics, with/without hypertension, with/without obesity, a remarkable worsening of renal function and the Charlson-comorbidity-index. Analyzing the Charlson-comorbidity-index, the group with "heavy comorbidity" presents a clear decline of postoperative OS in comparison to "no/light comorbidity" but without a statistically significant correlation (p=0.09). After correcting for the tumorstage in the multivariate analysis (Cox regression), an independent association on the postoperative OS cloud be shown for the intake of diuretics. There is a 2,5-fold increased risk of dying during the follow up for the intake of diuretics (hazard ratio 2,547; 95% confidence intervall, 1,283-5,056). For smoking, a strong but not significant correlation (p=0,07) could be shown in the multivariate analysis (hazard ratio 1,383 ; 95% confidence interval, 0,973-1,994). Thus, smoking and the permanent intake of diuretics, seems to be associated with a reduced OS and may be used as a thorough tool to evaluate the prognosis. The modifiable risk factors such as smoking and intake of diuretics should therefore be considered in postoperative recommendation to the behavior after surgical therapy as possible tertiary prevention. Present prognostic models don´t take these modifiable risk factors into consideration. Further studies are recommended to investigate and validate the influence of these modifiable risk factors on the postoperative overall survival.