Kidney or renal cell cancer is a disease in which malignant (cancer) cells are found in the lining of the tubules (tiny tubes) inside the kidney. Kidney cancer usually grows as a single mass or tumor inside the kidney. But a kidney can have more than one tumor. Sometimes tumors are found in both kidneys at the same time. Kidney tumors are often found on CT scans or ultrasounds being done for other concerns. Most of the time it is found before it has spread to other organs.

You have two kidneys, but a person can live with less than one complete kidney. Each kidney is a fist-sized, bean-shaped organ that’s located on either side of your backbone above your waist. Their main job is to filter your blood and help the body get rid of excess water, salt, and waste products. The waste is made into urine. Urine travels through long, thin tubes (called ureters) to the bladder where it is stored until you urinate.

Kidney cancer becomes more likely as you age. Risk factors include smoking, having certain genetic conditions, and misusing pain medicines for a long time.