The kidneys are two bean-shaped organs located in your abdomen, specifically on each side of your spine, in the lower part of the thorax between the 11th vertebra and the 3rd lumbar (the left kidney) and between the 12th vertebra and the space between the 3rd and 4th lumbar (the right kidney). The kidneys continually filter water, impurities and waste from the blood and produce urine. You need them to have a clean and healthy body.
Kidney cancer occurs when, due to certain factors, cancer cells grow abnormally in membrane that lines the small tubes within your kidneys. The causes of the transformation of healthy cells into cancerous are not clear to scientists, but risk factors are suspected (see Risk Factors).