OBJECTIVES: Despite GLOBOCAN project provides epidemiological data of kidney cancer worldwide, the current number of patients in Spain with advanced renal cell carcinoma (RCC) after first-line treatment remains unknown. The aim of this study was to estimate the total number of eligible patients for second and third-line treatment of advanced RCC in Spain, using published evidence and expert opinion consensus. METHODS: Incidence rates of kidney cancer for Spain were obtained from GLOBOCAN, assuming that RCC accounts for 90% of all kidney cancer and 25% of RCC patients are in stage IV at diagnosis. Prevalent patients with stage IV RCC or stage I-III RCC who relapsed after nephrectomy was estimated using Spanish incidence and mortality data. Stage I-III RCC patients who relapsed after nephrectomy were estimated using metastases free survival rate. Patients at disposition to receive active second and third-line treatments were estimated considering progression rates of 60% and 31% for first to second-line and second to third-line, respectively. In each treatment line, patients not receiving active treatment or recruited in clinical trials were excluded. RESULTS: