According to Turkish Statistical Institute data at the end of 2013 population of Turkey is approximately 80 million [5]. In the project of Turkey Association of Cancer Research Control which was named Cancer Record and Incidence shows that cancer incidence is 100-150 in 100.000 [6] and 2% of all new cancers are renal cell carcinoma [7]. There would be 1800 new RCC patients in 1 year, and according to the OS of the disease, there would be 4000 RCC patients in Turkey. 15% of these are metastatic at the time of diagnosis and 30-40% of these are metastatic after a period of a time [8]. Presuming that there are 1800 patients with metastatic renal carcinoma in Turkey, the minimum sample size with 7,6 confidence interval, 95% confidence level and 80% power was calculated as 152.