The Kidney

The kidneys are two bean-shaped organs located on either side of the body, just underneath the ribcage. The main role of the kidneys is to filter out waste products from the blood and to produce urine.

Kidney Cancer

Kidney cancer is the 6th most common cancer in Australian men and the 11th most common cancer in Australian women. Kidney tumours are usually found by chance when ultrasounds or CT scans are ordered to look for other disorders in the abdomen. Less commonly, they may cause blood in the urine, a lump that can be felt in the abdomen or abdominal pain. Kidney cancer usually affects only one kidney.

There are two broad types of kidney tumours;

  1. Renal Cell Carcinoma arises from the kidney tissue and account for about 85% of kidney tumours. These tumours are more common in people who are overweight and who smoke.
  2. Urothelial (Transitional Cell) Carcinoma arises in the drainage component of the kidney (the collecting system) and ureter tube. These tumours are more common in people who smoke, have a history of using a pain-killer called phenacetin (now banned) or who have worked with certain chemicals or dyes.

Other tumour types are rare, including sarcoma, lymphoma and metastastic deposits of other cancers.

Diagnosis:

When a kidney tumour is suspected a CT scan with contrast (dye injected into a vein) is most commonly used to visualize the area. Sometimes an ultrasound or MRI scan are used to get more detailed images.

If a Urothelial Carcinoma is suspected a series of urine tests to look for atypical cells (urine cytology) and an ureteroscopy (passage of a telescope into ureter tube and kidney) may be required to confirm the diagnosis.

A CT scan of the chest is used to rule out spread of cancer to the lungs. A bone scan may be ordered to rule out disease in the bones. A DMSA or MAG3 scan may be used to assess the function of each kidney prior to surgery.

Occasionally, if a diagnosis cannot be made with imaging it may be necessary to take a biopsy of the kidney under CT or ultra-sound guidance.

Treatment:

The primary form of treatment for most kidney cancers is surgery. The surgery required depends on the tumour type, size and where it is located in the kidney.

Active Surveillance:

For a very small tumour it may be possible to safely observe it over time. Small tumours that grow very slowly or do not change in size can be monitored with CT or ultrasound scans. By closely following these lesions it is possible to avoid surgery in some cases, but still identify when a tumour poses a risk and requires treatment.

Partial Nephrectomy:

For small kidney tumours (usually less than 4cm) is it sometimes possible to remove only the affected portion of the kidney. This allows for remaining, healthy kidney tissue to be preserved.   The suitability of a tumour for partial nephrectomy depends on the location of the lesion in the kidney and how the patient’s other kidney functions.

  • Open Partial Nephrectomy: An incision if made through the flank to allow access to the kidney. The kidney mass is removed and the normal tissue is preserved. A hospital stay of about 5 days is typical after this operation.
  • Robotic Partial Nephrectomy: The diseased portion of kidney is removed with keyhole surgery and the utilization of a surgical robot to allow for very precise and safe dissection. Recovery time is much shorter using keyhole surgery; it requires a hospital stay of 2-3 days.

Radical Nephrectomy

The whole kidney, adrenal gland and the surrounding fatty tissue are removed. This is the most common treatment for kidney cancer.

  • Laparoscopic or robotic nephrectomy: Keyhole surgery is used to remove the whole kidney and surrounding tissue. A larger incision (approximately 10cm) is made in the lower abdomen at the end of the operation, through which the kidney is removed in a specially designed bag. Typically this procedure would require a hospital stay of 2-3 nights.
  • Open nephrectomy: For very large tumours or tumours with extension into the renal vein or inferior vena cava (large abdominal veins) it may be necessary to perform an open operation. If there is extensive involvement of the veins a team of other surgeons may be involved, including a second urologist, a liver surgeon and a vascular surgeon.

Nephro-ureterectomy:

For Urothelial Carcinomas it is necessary to remove the whole kidney and the attached ureter tube, all the way down to the connection with the bladder. This operation is usually performed with keyhole surgery, but may require an incision over the bladder to complete the removal of the ureter. Because the ureter tube is detached from the bladder is it usually necessary to leave a urinary catheter to drain the bladder for several days to allow the bladder stitches to heal.

Other treatments:

Radio-Frequency Ablation (RFA):

For patients who are not well enough for an operation who have a small tumour (less than 4cm) it may be possible to use RFA. This procedure is performed by the radiology doctors, who pass needles through the back to deliver high intensity energy to the kidney tumour. This process destroys the cancer cells and causes the tumour to scar.

Systemic Therapies:

There are a number of medications that have been developed in recent years to treat kidney cancers that have spread beyond the kidney and are not suitable for surgery. These medications block certain cellular pathways to stop or slow cancer growth. If investigations show that the kidney cancer has spread beyond the kidney, your Urologist will refer you to a Medical Oncology doctor to discuss other treatment options.

Kidney Stones

The kidneys act to filter the blood, removing waste products and fluid that then pass as urine. The waste products can clump together as crystals that then build up to form rock-like stones within the kidney. Kidney stones can vary in size from tiny through to several centimeters in diameter.   Kidney stones cause pain when they block the flow of urine. There can be serious complications from kidney stones such as kidney failure or severe infections.

Treatment:

There are many treatment options available for kidney stones and these vary depending on the size, location and composition of the stone. Your Urologist will outline the most appropriate option for your circumstances.

Conservative management:

If the stone is small (less than 4mm) it may pass by itself without needing treatment over the course of a week or two. Depending on the location of the stone, medications can sometimes be used to maximize the chance of a small stone passing without an operation.

Insertion of ureteric stent:

If a stone is causes a blockage resulting in pain, kidney failure or infection it is important to relieve the obstruction by allowing the urine to drain past the stone. This procedure involves passing a telescope into the bladder, then using Xray guidance to pass a flexible wire past the stone causing the blockage. A stent (fine plastic tube) can then be passed over the wire to sit between the kidney and bladder and allow free flow of urine. Ureteric stents are temporary and allow any swelling around the stone to resolve, and for kidney failure and infection to be treated prior to treating the troublemaking stone.

On rare occasions, if a stone is tightly impacted, it may be not possible to pass a stent tube. If this is the case if may be necessary to pass a different tube (nephrostomy tube) through the back to allow the kidney to drain.

Stent tubes cause some people bothersome symptoms. For more information see our STENT INFORMATION SHEET.

Endoscopic Treatment:

Most stones can be treated by passing a fine telescope through the bladder and up into ureter tube or kidney with Xray guidance. A special basket device can be used to grasp and remove very small stones. In stones up to approximately 15mm in size a laser fibre can be used to break down the stones into tiny dust-like particles that can then pass in the urine. For larger stones it may be necessary to have more than one procedure to completely clear the stone.

Extracorporeal shock-wave lithotripsy (ESWL):

Ultrasound waves are directed through the skin into the kidney to break down the stones into smaller fragments that can pass in the urine. This technique is only suitable for some stone types, and tends to be used for stones located in the kidney.

Percutaneous Nephrolithotomy (PCNL):

For very large stones located in the kidney it may be necessary to pass a tube through the back to access the stone. A device using a combination of ultrasound and pneumatic power then grinds the stone to small fragments and removes the debris. After the procedure a temporary tube is placed through the back to allow the kidney to drain. This is usually removed after 48 hours.

Laparoscopic (Keyhole) Surgery:

Rarely, for more complex situations, such as very large stones in poorly functioning kidneys or very large stones blocking the ureter tube, is may be necessary to consider keyhole surgery to completely treat the problem.

Stone prevention:

Once a person has had one kidney stone they have a higher risk of forming more stones. Depending on the type of kidney stones it may be possible to reduce the risk of forming more stones.

Fluids:

As a general rule, the most important way to minimize the risk of stones is to avoid dehydration and maintain a high fluid intake. By keeping the urine dilute there is less opportunity for crystals in the urine to clump together. The amount of water or fluids you will need to drink will depend on your lifestyle and the climate, but as a general rule aim for 2 litres per day. In summertime in Queensland (especially if you do manual work or lots of exercise) you may need to increase your intake further.

For further information please refer to our STONE MINIMISATION INFORMATION.

Kidney Obstruction

A blockage to the outflow of the kidney, at the junction between in the kidney and the ureter tube is called a pelvic-ureteric junction (PUJ) obstruction. This may be caused by a blood vessel passing over the ureter tube at this level and causing a blockage or may be due to a malformation the patient was born with. Despite being present for the patient’s whole life, this condition will often not cause symptoms until well in to adulthood.

Symptoms that may indicate a PUJ obstruction include pain in the flank or side that is worse after drinking large volumes of fluids, recurrent infections or pain associated with kidney stones.

Diagnosis:

If you have symptoms of abdominal or flank pain your GP will often arrange an ultrasound scan or CT scan of your abdomen. This will reveal swelling in the drainage component of the kidney. Your Urologist with then arrange further tests to evaluate the drainage and function of your kidney. This may include a MAG3 or DTPA scan (nuclear medicine scans are assess how quickly the kidneys are able to drain urine and how well the kidneys work), contrast CT scan and blood tests.

These tests can exclude a blockage or confirm it. Rarely the tests may not give a definite answer and more tests are required.

Laparoscopic or Robotic Pyeloplasty:

If a blockage is confirmed and the kidney functions well, a procedure to remove the blocked segment and re-join the renal pelvis to the ureter can be completed with keyhole surgery. A stent tube will need to be placed during the operation to allow the urine to drain past the new join whilst it heals. This stent can be removed with a minor procedure a few weeks later.

Laparoscopic Nephrectomy:

If the blockage has caused irreparable damage to the kidney it is sometimes necessary to remove the entire kidney.