This prospective cohort study will investigate whether changes in circulating and urinary exosomal biomarkers (target exosomal miRNA) are associated with response to systemic treatment in patients with advanced renal cell carcinoma. Patients treated with immune checkpoint inhibitors or targeted therapies in the first-line or second-line setting will be included. Exosomal biomarker expression will be analyzed in blood and urine samples collected during the first 16 weeks of treatment. Treatment response will be assessed using standard radiological imaging. The study aims to determine whether changes in exosomal miRNA expression after treatment initiation can serve as predictive biomarkers of objective response in advanced kidney cancer.