What is kidney cancer?

Kidney cancer is a type of cancer that starts in the cells of the kidney.

Types of kidney cancer

About 9 out of 10 kidney cancers are renal cell carcinoma (RCC), sometimes called renal adenocarcinoma.

In the early stages, the primary cancer forms a tumour that is confined to the kidney. Usually, one kidney is affected, but in rare cases there is a tumour in both kidneys. As cancer grows, it can spread to areas near the kidney, such as the surrounding fatty tissue, veins, adrenal glands, lymph nodes, ureters or the liver. It may also spread to other parts of the body, such as the lungs or bones.

Very rarely, cancers in the kidney can be secondary cancer (metastasis) from primary cancer located in another part of the body. However, this type of cancer is not kidney cancer and it behaves more like original cancer.

Other types of kidney cancer include urothelial carcinoma and Wilms tumour (nephroblastoma).

How common is kidney cancer?

About 800 people are diagnosed with kidney cancer each year in Queensland. It makes up about 2.5% of all cancers.  The risk of kidney cancer increases with age, and most cases occur in people over 50.

Risk factors

The factors listed below may increase the risk of a person developing kidney cancer. However, having one or more of these risk factors does not mean you will develop cancer.

  • Smoking – People who smoke have almost twice the risk of developing kidney cancer as nonsmokers. Up to one in three of all kidney cancers are thought to be related to smoking.
  • Obesity – Too much body fat may cause changes to some hormones that can lead to kidney cancer.
  • High blood pressure – Whatever the cause, high blood pressure increases the risk of kidney cancer.
  • Kidney failure – People with end-stage kidney disease have a higher risk of developing kidney cancer.
  • Family history – People with a parent, brother or sister (first degree relative) with kidney cancer are at increased risk.
  • Inherited conditions – About 2-3% of kidney cancers occur in people who have particular inherited syndromes, including von Hippel-Lindau disease, hereditary papillary RCC, Birt-Hogg-Dube syndrome and Lynch syndrome.
  • Exposure to toxic substances at work – The risk may be higher after regular exposure to certain chemicals, such as metal degreasers, arsenic or cadmium.

Symptoms

Most people with kidney cancer have no symptoms and are often diagnosed with the disease when they see the doctor for an unrelated reason.

Symptoms can, however, include:

  • Blood in the urine (haematuria) – this may be obvious or the urine may just look dark, rusty or brown
  • Pain in the lower back or on one side that is not caused by injury
  • A lump in the abdomen
  • Constant tiredness
  • Unexplained weight loss
  • Fever (not caused by a cold or flu)

Cancer can affect the amount of hormones produced by the kidneys and this may lead to a low red blood cell count (anaemia), a high red blood cell count (polycythaemia) or high levels of calcium in the blood (hypercalcaemia). Sometimes these problems can cause symptoms such as fatigue, dizziness, headaches, constipation, abdominal pain and depression.

The symptoms listed can also occur with other illnesses, so they don’t necessarily mean you have kidney cancer – only tests can confirm the diagnosis. If you are concerned, make an appointment with your general practitioner (GP).

Diagnosis

Most kidney cancers are found by chance (incidentally) when a person has an ultrasound or another imaging scan for an unrelated reason.

If your doctor suspects you have kidney cancer, you will have some of the following tests but you are unlikely to need them all. You will probably have urine and blood tests to check your general health and look for signs of a problem in the kidneys, but these tests cannot diagnose kidney cancer.

The main tests for diagnosing kidney cancer are imaging scans and tissue sampling (biopsy). Sometimes the doctor will also recommend an internal examination of the bladder, ureters and kidneys.

You will usually have at least one of the following imaging scans:

  • Ultrasound – uses soundwaves to produce pictures of your internal organs.
  • CT scan – uses x-rays to take many pictures of the inside of your body and then a computer compiles them into one detailed, cross-sectional picture.
  • MRI scan – uses a powerful magnet and radio waves to create detailed, cross-sectional pictures of the inside of your body.
  • Radioisotope bone scan – a scan to see if any of the cancer has spread to the bones

A biopsy involves removing a tissue sample for examination under a microscope. It is a common way to diagnose cancer, but it not often needed for kidney cancer before treatment. This is because imaging scans are good at showing if a kidney tumour is cancer.

For many people with kidney cancer, the main treatment is surgery. In this case the tumour removed during surgery is tested to confirm that it is cancer.

Some tests may be repeated during or after treatment to check how well the treatment is working. Waiting for the test results can be a stressful time. It may help to talk to a friend or family member, a healthcare professional, or call Cancer Council 13 11 20.

Treatment

Your medical team will recommend a treatment based on what you want, your general health, the location of cancer and the extent that cancer has spread.

Treatments for kidney cancer include surgery and radiofrequency ablation. Other options might include stereotactic body radiation therapy (SBRT). In some cases, your doctor may recommend active surveillance.

Also known as observation, active surveillance is a way of monitoring kidney cancer. The aim is to avoid affecting how your kidney works and other side effects you may experience if you have surgery. It may be suggested if the tumour is less than 4cm in diameter. Active surveillance might also be an option if you are not well enough for surgery and the tumours are small, or if you are older.

Active surveillance involves having regular ultrasounds or CT scans. If these imaging tests suggest a tumour has grown, you may be offered active treatment (usually surgery).

Choosing active surveillance avoids treatment side effects, but you may feel anxious about having a cancer diagnosis without active treatment.  Talk to your doctors about ways to many any worries.

Surgery is the main treatment for early kidney cancer. The operation your doctor recommends will depend on the type of kidney cancer you have, your general health and the stage and grade of cancer.

Prognosis

Prognosis means the expected outcome of a disease. It is not possible for anyone to predict the exact course of the disease, but your doctor can give you an idea about common issues that affect people with kidney cancer.

In most cases, the earlier that kidney cancer is diagnosed, the better the chance of successful treatment. If the cancer is found after it has spread to other parts of the body, it is very unlikely that all the cancer can be removed, but treatment can often keep it under control.

People who can have surgery to remove cancer tend to have better outcomes. However, other factors such as your age, general fitness and medical history also affect prognosis.

Discussing your prognosis and thinking about the future can be challenging and stressful. It may help to talk with family and friends. You can also call Cancer Council 13 11 20 if you need more information or emotional support.

Support for Queenslanders

Whether you have been diagnosed with kidney cancer, or have a family member or friend who is affected by cancer, there are times when you may need support. Our professional services and support programs are here to help you.

Find out more about:

You don’t have to face cancer alone – we’re here to help.

Resources

For more information on kidney cancer please see these resources


If you are a patient, family or friend and would like to order a copy of the Understanding Kidney Cancer booklet, please call Cancer Council 13 11 20