What is Renal Cell Carcinoma (RCC)?
Most cancers are named after the part of the body where the cancer first begins. RCC is the most common
type of kidney cancer. Kidney cancer begins in the kidneys.1,2
The normal structure and function of the kidneys2
Structure of the kidney
The kidneys are a pair of bean-shaped organs, each about the size of a fist. They are attached to the upper back wall of the abdomen and protected by the lower rib cage. One kidney is just to the left and the other just to the right of the backbone.2
The upper and lower portions of each kidney are sometimes called the superior pole and inferior pole. A small organ called an adrenal gland sits on top of each kidney. Each kidney and adrenal gland are surrounded by fat and a thin, fibrous layer known as Gerota’s fascia.2
Function of the kidney
The kidneys’ main job is to remove excess water, salt, and waste products from blood coming in from the renal arteries. These substances become urine. Urine collects in the centre of each kidney in an area called the renal pelvis and then leaves the kidneys through long slender tubes called ureters. The ureters lead to the bladder, where the urine is stored until you urinate.2
The kidneys also:2
Control blood pressure by making a hormone called renin.
Regulate red blood cells by making a hormone called erythropoietin. This hormone tells the bone
marrow to make more red blood cells.
Our kidneys are important, but we can function with only one kidney.2
Some people do not have working kidneys at all and require a medical procedure called dialysis. The most
common form of dialysis uses a specially designed machine that filters blood much like a real kidney would.2
Types of Kidney Cancer
Renal cell carcinoma
Renal cell carcinoma (RCC) is also known as renal cell cancer or renal cell adenocarcinoma. It is the most common type of kidney cancer, with about 9 out of 10 kidney cancers being renal cell carcinomas.2
Although RCC usually grows as a single tumour within a kidney, there are sometimes there are 2 or more tumours in one kidney or even tumours in both kidneys at the same time.2
There are several subtypes of RCC, based mainly on how the cancer cells look in the laboratory. Knowing the subtype of RCC can be a factor in deciding treatment. Knowing the subtype of RCC can also help determine if the kidney cancer might be caused by an inherited genetic syndrome.2
Clear cell renal cell carcinoma2
This is the most common form of RCC. About 7 out of 10 people with RCC have this kind of cancer. The cells that make up clear cell RCC look very pale or clear.
Non-clear cell renal cell carcinomas2
Papillary RCC: This is the second most common subtype – about 1 in 10 RCCs are of this type. These cancers form little finger-like projections (called papillae) in some, if not most, of the tumour. Some doctors call these cancers chromophilic because the cells take in certain dyes and appear pink when looked at under the microscope.
Chromophobe RCC: This subtype accounts for about 5% (5 cases in 100) of RCCs. The cells of these cancers are also pale, like the clear cells, but are much larger and have certain other features that can be recognized when looked at very closely.
Rare types of RCC: These subtypes are very rare, each making up less than 1% of RCCs:
• Collecting duct RCC
• Multilocular cystic RCC
• Medullary carcinoma
• Mucinous tubular and spindle cell carcinoma
• Neuroblastoma-associated RCC
Unclassified RCC: Rarely, renal cell cancers are labelled as unclassified because the way they look doesn’t fit into any of the other categories or because there is more than one type of cancer cell present.
The exact cause of RCC is unknown, however there are certain risk factors that may be linked to it. These risk factors include:1,3
Smoking: The amount that you smoke is related to the risk of kidney cancer.
Asbestos: Studies show a link between exposure to asbestos and kidney cancer.
Cadmium: There may be a link between cadmium exposure and kidney cancer. Cadmium may also increase the cancer-causing effect of smoking.
Family history: Family history of kidney cancer increases a person’s risk.
Gender: Men are twice as likely to develop RCC than women.
Von Hippel-Lindau syndrome: A hereditary condition associated with a gene mutation. People with this condition often develop several kinds of tumours and cysts (fluid-filled sacs) in different parts of the body. They have an increased risk of developing clear cell RCC, especially at a younger age.
Birt-Hogg-Dube syndrome: A hereditary condition associated with a gene mutation. People with this syndrome develop many small benign skin tumours and have an increased risk of RCC. They may also have benign or malignant tumours of several other tissues.
Other hereditary syndromes: Patients with hereditary papillary RCC, hereditary leiomyoma-RCC, and hereditary renal oncocytoma are more likely to develop kidney cancer.
Obesity: Obesity may cause changes in certain hormones that can lead to RCC.
Advanced kidney disease: Patients with advanced kidney disease who have been on dialysis for a long period may develop RCC.
High blood pressure: Patients who have high blood pressure have a higher risk for kidney cancer.
In addition to a complete medical history and physical examination, diagnostic procedures for kidney cancer may include the following:1
Blood and urine laboratory tests.
Intravenous pyelogram (IVP): A series of X-rays of the kidney, ureters, and bladder with the injection of a contrast dye into the vein to detect tumours, abnormalities, kidney stones, or any obstructions, and to assess renal blood flow.
Renal angiography (also called arteriography): A series of X-rays with the injection of a contrast dye into a catheter, which is placed into the blood vessels of the kidney to detect any signs of blockage or abnormalities affecting the blood supply to the kidneys.
Other imaging tests (to show the difference between diseased and healthy tissues), including the
Based on the diagnostic results of other tests and procedures, a biopsy may be needed. A biopsy is a procedure in which a sample of the tumour is removed and sent to the laboratory for examination by a pathologist.1
In many cases, the cause of kidney cancer is not known. In some other cases (such as with inherited conditions), even when the cause is known it may not be preventable.4
Some ways to possibly reduce the risk of this disease include:4
Cigarette smoking is responsible for a large percentage of cases, so stopping smoking may lower the risk.4
Obesity and high blood pressure are also risk factors for RCC. Maintaining a healthy weight by exercising and choosing a diet high in fruits and vegetables may also reduce the chance of getting this disease.4
Avoiding exposure to harmful substances such as trichloroethylene, asbestos or cadmium at work, may also reduce the risk for RCC.4
Specific treatment for kidney cancer will be determined based on:1
Extent of the disease
Tolerance for specific medications, procedures, or therapies
Expectations for the course of the disease
Opinion or preference
Treatment may include:1
Surgery: A nephrectomy ( removal of the kidney) is the most common treatment for kidney cancer. The remaining kidney is generally able to perform the work of both kidneys.
The following are different types of nephrectomy procedures:
Radical nephrectomy: The whole kidney is removed along with the adrenal gland, tissue around the kidney, and sometimes, lymph nodes in the area.
Partial nephrectomy: Only the part of the kidney that contains the tumour is removed.
Simple nephrectomy: Only the kidney is removed.
Radiation therapy: Radiation therapy uses high-energy X-rays to kill cancer cells and is also sometimes used to relieve pain when kidney cancer has spread to the bone.
Targeted therapy: Targeted therapy uses drugs that attack specific parts of cancer cells. These drugs work differently from standard chemotherapy drugs and often have less severe side effects. They are commonly the first line of treatment for advanced kidney cancer.
Biological therapy (also called immunotherapy): Biological therapy is a treatment that uses the body’s own immune system to fight cancer.
Chemotherapy: Chemotherapy is the use of drugs to kill cancer cells. Unfortunately, kidney cancer is often resistant to chemotherapy drugs.
Arterial embolization: Arterial embolization is a procedure in which small pieces of a special gelatine sponge, or other material, are injected through a catheter to clog the main renal blood vessel. This procedure shrinks the tumour by depriving it of the oxygen-carrying blood and other substances it needs to grow. It may also be used before an operation to make surgery easier or to provide relief from pain when removal of the tumour is not possible.