Kidney cancer. Coloured computed Tomography (CT) scan, axial section, of the human abdomen showing kidney cancer. At centre is a vertebra (rust). The diseased kidney (right on image, orange) is distorted and enlarged by a cancer tumour. This diseased kidney with a blue coloured interior is non-functioning except for a small area excreting into the collecting system (yellow triangle, upper right). At lower left is a normal kidney (red, bean-shaped), that is excreting an X-ray contrast agent (yellow). The liver (brown, left) is next to the normal kidney, with the circular gall bladder (blue) covering the liver.