For patients with metastasized renal cell carcinoma (RCC), imaging techniques are of great importance. Currently, therapy widely relies on antiangiogenic factors, which frequently lead to relatively subtle changes in the size of lesions. From this aspect the commonly used RECIST criteria (response evaluation criteria in solid tumors) must be considered as imprecise for the evaluation of the response to therapy. This article gives a review on new software-based volumetric methods, which allow therapy-induced changes in the size of metastases from RCC to be detected with higher sensitivity and reproducibility. A comparison of RECIST and volumetry was carried out with data from patients with metastasized RCC to demonstrate the higher sensitivity of the 3D volumetric procedure.