Kidney cancer

What is kidney cancer?

Kidney cancer is a malignant cell growth (a tumour) in the kidneys. Its medical name is renal cell carcinoma. A tumour in the kidney can also be benign (non-cancerous).

Kidney cancer is a general term. There are many variations of tumours in the kidney and stages of the disease. Your treatment and experience depend on the specific characteristics of the tumour and the expertise of your medical team.

Kidney cancer represents around 2% of all cancer diagnoses worldwide. In the last twenty years, the number of cases of kidney cancer worldwide has increased slightly, but the survival rate has also gone up in most of the region. Because of the more frequent use and improvements in ultrasound and CT imaging technology, more kidney cancers are now diagnosed at an earlier stage.

Men are more likely to be diagnosed with kidney cancer than women. Most people are diagnosed between the ages of 60 and 70.

Stages of kidney cancer

There are different stages of kidney cancer. If the tumour is limited to the kidney and has not spread, this is called localised kidney cancer. In locally advanced kidney cancer, the tumour has grown out of the kidneys into surrounding tissue and invaded veins, the adrenal gland, or lymph nodes. Doctors speak of metastatic disease if the cancer has spread either to distant lymph nodes or other organs.

Risk factors for kidney cancer

The causes of kidney cancer are often difficult to determine. General risk factors are smoking and obesity.

Having a first-degree relative with kidney cancer or high blood pressure are also potential risk factors. Certain lifestyle changes, most importantly quitting smoking and keeping a healthy weight, may reduce the risk of developing kidney cancer.

What is the function of the kidneys?

The kidneys are two bean-shaped organs in the back of the abdomen which filter your blood and produce urine. They are important for various processes in the body, including regulating your blood pressure, the production of blood cells, and keeping your bones healthy (Fig. 1).

A kidney and its surrounding tissue, veins, and arteries.
Fig 1: A kidney and its surrounding tissue, veins, and arteries.

Symptoms and diagnosis

In most cases kidney cancer is asymptomatic, which means that there are no clear symptoms to indicate it. Most kidney tumours are found during a routine ultrasound or a similar imaging procedure for other conditions such as back pain.

Because there are several types of kidney tumours, the doctor does a series of tests to better understand your specific situation. These tests include a medical history, laboratory tests and scans. Sometimes a family history is also taken. A CT scan or MRI scan will reveal the size of the tumour and if it has invaded local veins, lymph nodes, or surrounding organs. This is important to determine further treatment. The doctor may also perform a physical examination and take blood and urine for testing.

With the results of your scan, the urologist can define the stage of the disease. By analysing tumour tissue, received either during surgery or biopsy, the pathologist determines the subtype of the tumour and whether or not it is an aggressive form. Together, the stage, subtype, and aggressiveness of the tumour form the classification.

Classification of the kidney tumour is used to estimate your individual prognosis. Based on this individual
prognosis your doctor will discuss the best treatment pathway for you. In some cases you may need additional tests to check your kidney function. This is important if you only have one kidney or if you are at risk of kidney failure because you have diabetes, high blood pressure, chronic infections, or a kidney disease.

Symptoms

While kidney cancer is generally asymptomatic, about 1 in 10 people do experience symptoms like pain in the side of the body, abdominal mass or blood in the urine. This could be a sign that the disease has advanced. Some people can also experience so-called paraneoplastic syndromes. These are reactions the body can have to any type of cancer and may include high blood pressure, weight loss, fever, anaemia, muscle mass loss, and loss of appetite. Syndromes more commonly associated with kidney cancer include changes in liver enzymes and blood platelets. These changes are usually discovered during tests and normally do not cause any symptoms.

Bone pain or a persistent cough could be signs that the cancer has spread through the body. This is known as metastatic disease.

Diagnostics

In most cases kidney cancer is asymptomatic, which means that there are no clear symptoms to indicate it. Most kidney tumours are found during a routine ultrasound or a similar imaging procedure for other conditions such as back pain.

Because there are several types of kidney tumours, the doctor does a series of tests to better understand your specific situation. These tests include a medical history, laboratory tests and scans. Sometimes a family history is also taken. A CT scan or MRI scan will reveal the size of the tumour and if it has invaded local veins, lymph nodes, or surrounding organs. This is important to determine further treatment. The doctor may also perform a physical examination and take blood and urine for testing.

With the results of your scan, the urologist can define the stage of the disease. By analysing tumour tissue, received either during surgery or biopsy, the pathologist determines the subtype of the tumour and whether or not it is an aggressive form. Together, the stage, subtype, and aggressiveness of the tumour form the classification.

Classification of the kidney tumour is used to estimate your individual prognosis. Based on this individual prognosis your doctor will discuss the best treatment pathway for you.

In some cases you may need additional tests to check your kidney function. This is important if you only have one kidney or if you are at risk of kidney failure because you have diabetes, high blood pressure, chronic infections, or a kidney disease.

Imaging is important for the diagnosis and classification of kidney tumours. Most common imaging techniques are ultrasound, CT scans, and MRI. In some cases a biopsy is done to get more insight into the specific characteristics of the tumour.

Read more about contrast-enhanced scan

After a tumour is detected, the doctor first needs to know whether it is malignant. A contrast-enhanced ultrasound, CT, or MRI scan of the abdomen and pelvis provides information about this. CT and MRI scans also show:

  • The location and size of the tumour
  • Whether or not you have enlarged lymph nodes
  • Whether or not the tumour has spread to neighbouring organs, such as the adrenal gland, liver, spleen or pancreas
  • Whether the urinary tract is affected by the tumour

For a contrast-enhanced scan, a contrast medium is administered through an IV, usually in your arm. The contrast medium highlights your veins and arteries by giving them a different colour in the pictures taken during the scan. This type of scan allows the radiologist to analyse the tumour. The results will guide the treatment you receive.

If you are allergic to contrast medium, you will receive an MRI or CT scan without contrast enhancement.

If your doctor thinks the cancer may have spread to the lungs, you will get further tests, like a CT scan. You may need a bone or brain scan if you have symptoms such as bone pain or epileptic seizures. These scans are done to see whether the cancer has spread to bones or the brain.

Read more about renal biopsy

During a renal tumour biopsy, one or more samples of tumour tissue are taken. First you receive local anaesthesia. Then the doctor inserts a needle through your skin and uses ultrasound or CT imaging to locate the tumour. The tissue samples are analysed by the pathologist in order to help determine future treatment.

Renal biopsy is not standard procedure in the diagnosis of kidney cancer. You may need a biopsy in case:

  • The results of your scan are not clear enough
  • You have a small tumour which could be treated with active surveillance
  • You have a small tumour which could be treated with radiofrequency ablation or cryotherapy

Biopsies may cause blood in the urine. In rare cases they can cause more severe bleeding. A renal tumour biopsy is generally a harmless procedure.

Classification

Kidney tumours are classified according to their stage, subtype, and the grade of aggressiveness of the tumour cells. These three elements are the basis for your possible treatment pathway.

Read more about kidney cancer classification

Staging system

Tumour stage indicates how advanced the tumour is and whether or not there are metastases in the lymph nodes or other organs.

Kidney tumour stage is based on the Tumour Node Metastasis (TNM) classification. The urologist looks at the size and invasiveness of the tumour (T) and determines how advanced it is, based on 4 stages. Whether any lymph nodes are affected (N) or if the cancer has spread to any other parts of your body (M) is also checked. If kidney tumours metastasise they generally spread to the lungs, or to the bones or brain. Figures 1 to 5 illustrate the different stages.

Tumour subtype

Next to staging, the subtype of kidney tumours is important. The subtype is determined by a pathologist, this is known as histopathological analysis. The specialist examines the tumour tissue either taken during a biopsy or after it has been removed during surgery. Renal biopsy is not a standard procedure in the diagnosis of kidney cancer. In most cases the subtype of your tumour will not be known until after you have surgery.

There are various subtypes of kidney tumours. Most kidney tumours are renal cell carcinomas (about 80-85%). Of these, the most common subtype is clear cell renal cell carcinoma (80%), 10% are papillary renal cell carcinomas, and 5% chromophobe renal cell carcinomas. The remaining 5% of renal cell carcinomas include collecting duct renal cell carcinoma (or Duct-Bellini-Carcinoma) and a variety of uncommon and hereditary carcinomas.

If you are diagnosed with a rare kidney tumour your doctor will give you detailed information about different treatment possibilities. These may differ from therapy for the more common kidney cancer subtypes. Treatment options are discussed by a multidisciplinary team of doctors, to find the best approach for you (See: The medical team).

The medical team

  • Urologist: a urologist specialises in health and diseases of the urinary tract
  • Oncologist: an oncologist specialises in all types of cancer
  • Onco-urologist: an onco-urologist specialises in urological cancers of, for instance, the bladder, kidney, prostate, or testicles
  • Pathologist: a pathologist studies tissue, blood, or urine to understand the specific characteristics of diseases. In cancer treatment, the pathologist helps with the classification of tumours
  • Radiologist: a radiologist specialises in imaging techniques and analyses ultrasound, T, MRI, or other scans done to diagnose or monitor a tumour
Fig. 1: A stage I kidney tumour is a tumour up to 7 cm,

Fig 1: A stage I kidney tumour is a tumour up to 7 cm, limited to the kidney.

Fig. 2: Stage II tumours are still limited to the kidney,

Fig. 2: Stage II tumours are still limited to the kidney but are larger than 7 cm.

Fig. 3: Stage III tumours have spread into the renal vein, the fatty tissue next to the kidney (perirenal fat), or the vena cava.

Fig. 4: Stage IV tumours have spread further outside of the kidney, beyond the renal fascia and into the adrenal gland. Sometimes, one or more lymph nodes are enlarged in this stage.

Treatment

If you are diagnosed with localised kidney cancer, your doctor can recommend treating the cancer with partial nephrectomy, radical nephrectomy, active surveillance, radiofrequency ablation, or cryotherapy. Each procedure has its own advantages and disadvantages. The choice of treatment depends on your individual situation.

This section describes the different treatment options, which you should discuss with your doctor.

This is general information which is not specified to your individual needs. Keep in mind that situations can vary in different countries.

If you are diagnosed with locally-advanced kidney cancer, your doctor can recommend to treat the cancer with radical nephrectomy or embolisation. Each procedure has its own advantages and disadvantages. The choice of treatment depends on your individual situation.

Kidney tumours can spread to other organs or distant lymph nodes. This is called metastatic disease. In metastatic disease, the kidney tumour is referred to as the primary tumour and the tumours in other organs are called metastases. Your doctor may recommend to treat metastatic disease with surgery, usually in combination with antiangiogenic therapy, also known as targeted therapy. In rare cases, immunotherapy is also used. For the treatment of metastases, radiotherapy may be recommended.

Generally, metastatic disease cannot be cured. The treatment of metastatic disease aims to reduce the size of the primary tumour and the metastases. This will give you the chance to live longer and have fewer symptoms.

Fig. 1: A stage I kidney tumour is a tumour up to 7 cm,
Fig. 2: Stage II tumours are still limited to the kidney,
Fig. 1: Metastatic kidney cancer can spread to the lungs, bones, or brain.
Fig. 7: Metastatic kidney cancer can spread to the lungs, bones, or brain.

Palliative care

Sometimes recovery from kidney cancer is not possible. When treatment is no longer successful you may be offered palliative care to make you more comfortable. Palliative care is a concept of care with the goal to optimise your quality of life if you cannot recover from your illness.

Palliative care is a concept of care with the goal to optimize your quality of life if you cannot recover from your illness. During palliative care you and your loved ones are supported by a multidisciplinary team. Together you address physical, psychological, social, and spiritual questions. Palliative care includes controlling your symptoms and medical treatment for pain management.

The palliative care team can provide care in the hospital or at your home. Another option is hospice care. A hospice is an institution which provides care during the final phase of your life.

In need of support?

The International Kidney Cancer Coalition (IKCC) is a global collaboration of patient organisations dedicated to kidney cancer patients.

This information was produced by the European Association of Urology, May 2014.

  • Dr. Bülent Akdogan,  Ankara (TR)
  • Dr. Sabine D. Brookman-May, Munich (DE)
  • Prof.Dr. Martin Marszalek, Vienna (AT)
  • Dr. Andrea Minervini, Florence (IT)
  • Prof. Haluk Özen, Ankara (TR)
  • Dr. Alessandro Volpe, Novara (IT)
  • Ms. Bodil Westman, Stockholm (SE)

This information was updated by the EAU Patient Information Working Group, March 2018.