Fig. 1

A representative case of a renal cell carcinoma. a Demonstrates a representative image before radiotherapy and b the treatment plan with exemplary planning computed tomography image in axial view with the treatment plan. Single fraction 25 Gy was prescribed to 70% isodose line (in green) to treat planning target volume shown in red line. The yellow and white circle lines represent the remaining isodose lines until 20% in blue. c shows an image 2 years after robotic stereotactic ablative radiotherapy