What are the kidneys?
The kidneys are bean-shaped organs located below the ribcage near the middle of your back. Most people have two kidneys, each about the size of a fist, one on each side of the spine.
What Happens Kidney Under Normal Conditions?
Healthy kidneys work around the clock to clean our blood. The kidneys look like 2 bean-shaped organs. They are found near the middle of the back below the rib cage. They are surrounded by a protective sac called the Gerota's fascia and a layer of fat. The renal artery brings “dirty” blood into the kidney. The renal vein takes clean blood out to the heart.
Our kidneys are our body’s main filter. They clean about 150 quarts of blood daily. Every day, they remove about 1-2 quarts of water and waste from the blood in the form of urine. Urine then moves into the kidney’s collecting system, the renal pelvis. It flows from there through the ureters to the bladder to be stored. Eventually it is pushed out of our bodies through the urethra.
The adrenal glands are on top of the kidneys. The adrenal glands regulate blood sugar, potassium, body fluids and sex hormones. They control our stress response by producing a hormone called adrenaline. They create a hormone called erythropoietin that helps to produce red blood cells.
As a filter, the kidney controls many things to keep us healthy:
- Fluid balance
- Electrolyte levels (e.g., sodium, potassium, calcium, magnesium, acid)
- Waste removal in the form of urine
- The regulation of blood pressure and red blood cell counts
When the kidneys are damaged they may not work well. In most cases, some damage won’t cause too many problems. But, major damage may need more treatment, like dialysis.
What is kidney cancer?
Kidney cancer is the abnormal growth of cells in kidney tissue. In time, these cells form a mass called a tumor. Cancer begins when something triggers a change in the cells, and they divide out of control. A cancerous, or malignant, tumor can spread (metastasize) to other tissues and vital organs.
What are the types of kidney cancer?
The information in this document refers to renal cell carcinoma – the most common form of kidney cancer. However, there are different types of kidney cancer, including:
- Renal cell carcinoma (RCC): This is the most common form of kidney cancer in adults and accounts for 85% of all kidney cancers. Renal cell carcinoma usually develops as a single tumor in one kidney, but it can affect both kidneys. Renal cell carcinoma begins in the cells that line the small tubes that are part of the nephrons within the kidneys. (Renal is the Latin word for kidney, and the term "carcinoma" refers to cancer that begins in the cells that line or cover an organ.)
- Transitional cell carcinoma: Transitional cell carcinoma accounts for 6% to 7% of all kidney cancers. This cancer usually begins in the area where the ureter connects to the main part of the kidney. This area is called the renal pelvis. Transitional cell carcinoma also can occur in the ureters or bladder.
- Renal sarcoma: This is the least common form of kidney cancer, accounting for only 1% of kidney cancer cases. It begins in the connective tissues of the kidneys and, if not treated, can spread to nearby organs and bones.
- Wilms' tumor: This is the most common type of kidney cancer in children. It accounts for about 5% of kidney cancers.
What are the treatments for kidney cancer (renal cell cancer)?
Treatment options which may be considered include surgery, radiotherapy, arterial embolisation and immunotherapy. (In general, chemotherapy does not work as well for renal cell cancer as for some other types of cancer. Therefore, it is not often used as a treatment.)
An operation to remove some (or sometimes all) of the affected kidney is the most common treatment. This is usually done as an open operation but it can also be done as a keyhole operation for some cases. If the cancer is at an early stage and has not spread then surgery alone may be curative. If the cancer has spread to other parts of the body, surgery to remove the affected kidney may still be advised, often in addition to other treatments.
Radiotherapy is a treatment which uses high-energy beams of radiation which are focused on cancerous (malignant) tissue. This kills cancer cells, or stops cancer cells from multiplying. See separate leaflet called Radiotherapy for more details. Radiotherapy may be advised in addition to surgery, which aims to kill any cancerous cells which may have been left behind following an operation.
3. Arterial embolisation
This may be used instead of surgery (for example, if you are not well enough for surgery). The aim of this treatment is to block off the blood vessel (artery) which is supplying a kidney tumour with blood. To do this, a catheter is inserted into a blood vessel in the groin. (A catheter is a long thin, flexible, hollow tube.) Using X-ray pictures for guidance, the catheter is pushed up into the blood vessel in the affected kidney. When it is in the correct place, a substance is injected down the catheter into the blood vessel to block the blood vessel. The tumour is then deprived of its blood supply and so dies.
4. Immunotherapy (sometimes called biological therapy)
This treatment uses medicines to stimulate the immune system to attack cancerous cells. Two medicines are commonly used to treat kidney cancer - interferon and aldesleukin (sometimes called interleukin 2).
Other immune therapies, such as using vaccines to stimulate your immune system to fight cancer cells and using monoclonal antibodies to attack cancer cells, are being investigated as possible new treatments for kidney cancer.
5. Other treatments
Using local anaesthetic with sedation or a general anaesthetic, radiofrequency (using electrodes inserted through the skin) or cryotherapy (using probes inserted through the skin or in a laparoscope) may be used as an option in the treatment of kidney cancer. Radiofrequency is delivered via an electrode to destroy the tumour tissue in the target area. Cryotherapy involves using a coolant at subfreezing temperatures to create an ice ball around the probe's tip, which then destroys surrounding tissue. Irreversible electroporation uses electricity to damage cancer cells. These treatments may only be available at specialist centres where the doctors are trained to do them.