A nephrectomy is an operation to remove one of the two bean-shaped kidneys that sit at the back of the abdominal cavity. The kidneys make urine by filtering waste products and excess fluid from the blood. Urine drains from the kidneys, through the ureters into the bladder where it is stored until the person is ready to go to the toilet.

A nephrectomy involves removing an entire kidney through an incision in the flank, the side of the body between the ribs and the hip. In a small number of cases if a person has poor kidney function or if they only have one kidney, a partial nephrectomy may be done which means only part of the kidney is removed.

A nephrectomy is usually done for one of two reasons, either for cancer of the kidney or because of a non-functioning kidney.

• In the case of kidney cancer a radical nephrectomy is done. A radical nephrectomy is done in an attempt to rid the body of cancer by removing the entire kidney, adrenal gland, protective shell with its surrounding fat and attached vessels. In more advanced cases it may be done to stop continued bleeding from the effected kidney.
   
• For non-functioning kidneys, which are either caused by large stones, a lack of blood supply or abnormal kidney structure, a simple nephrectomy is done. With a simple nephrectomy only the kidney itself it taken from within its protective shell and the adrenal gland and other structures are left behind. A simple nephrectomy is usually done to avoid recurrent infection and the possibility of severe illness because of infection.