Kidney cancer is diagnosed in over 300,000 people worldwide every year. Kidney cancer is the 12th most common cancer in the world, the same numbers as pancreatic cancer. Fewer than 1 in 20 people with cancer have kidney cancer, meaning that it is quite a rare disease.
For more information about kidney cancer statistics by country, click here.
In this section you will learn more about the different types of kidney cancer, the known causes of kidney cancer and how kidney cancer can be treated from the early stages to more advanced disease. There is still a need for more research and new treatments for many types of kidney cancer.
This information provides context for various therapies, including some of the newer immuno-oncology therapies that are being researched.
Cancer, tumour, mass, lump, bump, swelling, spot, shadow, lesion... You might have heard a number of these words to describe cancer. A more formal word is neoplasm, which means “new growth”. Medical experts might define cancer as a "neoplasm of abnormal tissue, the growth of which exceeds and is uncoordinated with normal tissue and persists once the stimulus for its growth is removed”.
Our bodies are made up of cells. Each tissue, each organ, every part of our body is made of these cells, which are all very different depending if they are in the liver, heart, blood or kidney. Our bodies are always making new cells: so we can grow, to replace worn-out cells, or to heal damaged cells after injury. Usually this process is very controlled.
For example, when you get a cut, skin cells receive a ‘go’ signal to start dividing. When the cut has healed, the skin cells get a ‘stop’ signal and stop dividing. This process is controlled by instructions and recipes within the cells, the so called “genes”. All cancers are caused by changes to these genes, called mutations.
Changes to genes that cause cancer usually happen during our lifetime, although a small number of people inherit these changes from a parent. There are many different types of cancer and cancer can affect almost any organ in the body. Where the cancer is, what type of tumour you have and what genetic mutations have caused the cancer could influence what treatment is best for that cancer.
Kidney cancer describes all tumours that form in the kidney. But not all kidney cancers are the same. It’s important to know the type of kidney cancer you have (see Question 3). Cancers that come from the lining of the ureter, the tube that runs down from the kidney to the bladder, are typically more like bladder cancers, and so are usually not called kidney cancer.
Mutations that cause cancer usually accumulate during our lifetime, so like most cancers, kidney cancer tends to occur in older people. The average age of people found to have kidney cancer is 55 years. Kidney cancer is rare in children. Kidney cancers begin small and can grow larger over time. Kidney cancers usually grow as a single mass but more than one tumour may occur in one or both kidneys.
If kidney cancer is treated in its early stages it is most likely to be cured. If kidney cancer cells spread, they may spread into surrounding tissue or to other parts of the body. When kidney cells reach a new organ or bone they might continue to grow and form another tumour (a “metastasis”) at that site. Primary cancer is a cancer that has formed in an organ (in this case the kidney) but has not spread elsewhere. Other words like “localised” or “early” apply if the primary cancer has not spread. Advanced (or metastatic) kidney cancer is the same cancer that started in the kidney, but has now spread somewhere else.
These secondary cancers or "metastases" or “mets” are still made up of kidney cancer cells even if they appear in the lung or elsewhere in the body. It is rare for a cancer from another part of the body to spread to the kidney.
Not all kidney cancers are the same.
All of these factors can affect:
The main histologies are:
The stage of a cancer describes the size of the cancer, and whether or not it has spread. This helps to guide treatment and can help plan long-term follow-up care. When staging is based on clinical assessment alone, it is referred to as the clinical stage. Microscopic examination of the affected tissue determines the “pathologic” stage. A staging system is a standardised way in which the cancer care team describes the extent of the cancer.
Your doctor will determine the "stage" of your kidney cancer based on:
The four main stages of kidney cancer below are based on this TNM staging system, which is one of the methods for ‘staging’ kidney cancer.
The cancer is only within the kidney and has not spread.
The cancer is less than 7cm in size.
If the cancer can be removed it is most likely to be cured with surgery.
9 out of 10 people will be alive and free of the cancer at five years after an operation.
The cancer is larger than 7cm but is still confined to the kidney and has not spread outside of the kidney.
Surgery is a good treatment option.
The five year survival rate is still very high after surgery for stage 2 kidney cancer.
The kidney cancer has moved nearby outside the kidney, but has not spread to distant organs.
For example, the cancer might have spread into the fat around the kidney, into the blood vessel coming out of the kidney, or into lymph nodes near the kidney. Surgery is often the right treatment. The chance of being cured by surgery is lower, but not zero.
The kidney cancer has spread widely outside the kidney; to the abdominal cavity, to the adrenal glands, to distant lymph nodes or to other organs, such as the lungs, liver, bones, or brain. This stage of cancer is very unlikely to be cured at the present time, but various treatments can help.
Like most cancers, kidney cancer is caused by mutations that accumulate over time in your body. Like most other cancers kidney cancer most often arises in older people and it is mostly a disease seen in adults over 40. There are a number of other risk factors that are important in the development of kidney cancer:
Smoking: Smoking doubles the risk of developing kidney cancer. This reduces back to population risk levels if the person stops smoking. Quitting at any time, at any age is a great idea. It’s never too late.
Gender: Men are twice as likely to be diagnosed with kidney cancer as women.
Obesity: Being very overweight or obese appears to be associated with an increased risk of developing kidney cancer in both men and women.
High blood pressure (hypertension): High blood pressure has been found to be a risk factor for kidney cancer.
Kidney stones: Having kidney stones is associated with a higher risk of developing kidney cancer in men.
Occupational exposure to toxic compounds: People regularly exposed to certain chemicals may have an increased risk of kidney cancer. These include asbestos, lead, cadmium, dry-cleaning solvents, herbicides, benzene or organic solvents and petroleum products, as well as people who work in the iron and steel industries.
Long-term dialysis and acquired cystic disease: Being on dialysis treatment over a long period of time may cause kidney cysts. Kidney cancer may develop from the cells that line these cysts.
People who have family members with kidney cancer, especially a sibling, are at increased risk. This can be due to genes that pass down from parent to child. Inherited gene mutations cause only 3-5% of kidney cancer.
Signs that your kidney cancer might be hereditary include:
If you have any one of these risk factors and think you may have a hereditary kidney cancer , speak to your physician.
There are several different types of hereditary kidney cancer. In the future we may have more information about new genes that cause kidney cancer. In the meantime, if you think your kidney cancer could be hereditary, speak with your doctor.
If there is a history of kidney cancer in your family, it is important that you tell your doctor so you can be tested. If the test shows that you do have a hereditary type of kidney cancer, other members of your family can be tested so that any sign of cancer could be treated early when it is most curable.
In rare cases, children can get kidney cancer, but they usually develop different types of kidney cancer to adults. The most common types of childhood kidney cancer are Wilms tumour and nephroblastoma. However, there have been rare cases of children with RCC or adults with Wilms tumour. In addition, there are other, mostly benign kidney tumours.
Many kidney cancers do not cause symptoms; they are found incidentally during a scan, X-ray or ultrasound that was ordered for another problem. When kidney cancer does cause symptoms these can be non-specific, that is, many of the symptoms that kidney cancer might cause can be mistakenly attributed to other causes, like a urine infection or a muscle twinge.
Most kidney cancer does not cause pain until advanced stages when it has started to spread. Many people with kidney cancer are not aware they have a tumour until they have a test for another health problem.
All of these symptoms can also be caused by other diseases. If you have any of these symptoms it is important to see your doctor so you can find out what’s causing them.
Kidney cancer is most often detected by chance, but if you have some of the symptoms listed above, speak with your doctor. As with all cancers, early detection can improve the chance of successful treatment and long-term outcomes. Your doctor may use different approaches, tests and investigations to diagnose kidney cancer, depending on the symptoms you display.
The most common tests that may be ordered include:
The majority of kidney cancers are initially discovered by scans (ultrasound, CT scan, or MRI), showing something like a “lump” on the kidney. This does not prove it is kidney cancer however, and it must be examined under the microscope to be sure. Sometimes your doctor may be so suspicious they recommend immediate surgery; other times your doctor might order a biopsy. During a biopsy, a thin needle is used to remove some cells from the tumour. A doctor will then look at the cells to see if they are cancerous or not. Up to 20% of small kidney masses (or lumps) are non-cancerous.
It may seem strange, but for some people with small (stage 1) kidney cancers, the first best treatment is often observation, or “active surveillance”. If you are older, or have significant medical problems, it may be safer to first carefully watch the cancer, with multiple scans and multiple visits to the cancer specialist. Because many kidney cancers are discovered by accident on scans that were recommended for other reasons, a number of small kidney lumps are now being detected. Kidney cancers that are smaller than 3cm are very unlikely to spread elsewhere, and sometimes the risk of dying during an operation outweighs the benefits of surgery. People who choose active surveillance with their doctors must continue to have regular follow-up care, in case the cancer starts to grow.
If you have a larger cancer in the kidney, surgery is usually the first best treatment. Surgery to remove kidney cancers is performed by a specialist surgeon called a Urologist or Uro-oncologist (a Urologist who specialises in cancer). Surgery may either remove just a part of the kidney (called a “partial nephrectomy”) or the entire kidney, which is called a “radical nephrectomy”. Surgery might need to be done with a large incision (an “open” nephrectomy) or might be able to be done by keyhole surgery (a “laparoscopic” nephrectomy) which results in a shorter hospital stay and quicker recovery. If the cancer is small (stage 1, <7cm) a “partial” nephrectomy may be possible, where the remaining normal kidney can be spared. If the cancer is larger (stage 2), or has started to spread near the kidney (stage 3) then the whole kidney is removed.
In some people an operation is not possible due to their age or other medical problems. It may be still possible to treat a localised kidney cancer without surgery, using other treatments. These include:
If you have one of the inherited types of kidney cancer, it is possible you may get more kidney tumours in the future. Because of this, your surgeon might suggest a different approach for you. Patients with inherited types of kidney cancer need a long-term strategy and so should be seen by an expert in kidney cancer whenever possible.
In many cancers, people can take additional “insurance policy” treatments to reduce the chance of the cancer coming back. You may have heard of chemotherapy, hormone therapy or radiotherapy as additional (“adjuvant”) treatments for cancer. These treatments do not seem to work for patients with kidney cancer, and recent clinical trials of typical kidney cancer drugs (e.g. sunitinib, sorafenib) have also failed to show a benefit for patients as additional, adjuvant treatments to help prevent recurrence.
All cancer survivors should have follow-up care. Once you have finished your cancer treatment, you will establish a follow-up cancer care plan with your treatment team, which may include seeing a range of health professionals.
In general, kidney cancer survivors usually return to their specialist every three to four months during the first few years after treatment, and once or twice a year after that. At these visits, your doctor will look for side effects from treatment and will check to ensure you cancer has not returned (recurred) or spread (metastasised) to another part of your body. The type of tests will depend upon your stage and grade of kidney cancer. Like most cancers, the chance of the cancer returning is highest soon after treatment. The longer away from the treatment, the more chance the cancer will not recur. However, your treatment team will want to follow you for some time. In some countries, kidney cancer patients are followed for 5 years following initial surgery. Your patient organisation can refer you to guidelines for follow-up that are specific to kidney cancer in your country or other countries.
In people with advanced kidney cancer, where the cancer has spread to distant organs, the cancer is usually not curable. The goal of treatment is therefore to make life as long and as normal as possible. Combinations of different treatments may be recommended by different doctors, including urologists, medical oncologists who prescribe anti-cancer medications, and radiation oncologists who treat people with radiation. Throughout, this team of specialists will work with you and your family doctor to help you control your symptoms and live as normal a life as possible. Treatments for advanced kidney cancer include:
In some people in whom the kidney cancer has spread, the cancer might be growing so slowly that the right first option is to watch carefully. This is especially the case when the cancer has been discovered by accident. If the cancer starts to grow quickly or cause symptoms then active treatments will be recommended. A small percentage of patients might live without symptoms from the cancer for a very long time, sometimes years, so your doctor might advise you to observe for a period of time, in case this applies to you.
A clinical trial is sometimes erroneously perceived as a “last resort”, but with rapidly improving treatments it should be considered the “first port of call”. A clinical trial is a way of testing new treatments, or old treatments used in a new way. Clinical trials are not right for every person; not every person is right for a clinical trial. If a clinical trial is available it can be an interesting opportunity to consider. One always hopes that the new treatment will improve on standard treatments, but sometimes it works no better than before. Talk to your doctor to find out about clinical trials or use some of the tips in the section "Discovering IO clinical trials" to identify clinical trials that might be right for you.
In a very small number of people, the cancer spreads to only one or two places; if this is the case it can be possible to try to cut out all the cancers (a “metastectomy”). Some patients can live a very long time in these circumstances, but it really only applies to patients where there is only one or two spots elsewhere and they can all be safely removed.
Surgery does not usually cure kidney cancer that has spread, but it may be recommended to prevent symptoms and problems from the cancer. However, if the kidney cancer that has spread is not causing a lot of problems, and your health is otherwise good, there is evidence that removing the original cancer in the kidney improves survival and helps other treatments work better. This “cytoreductive” nephrectomy would be performed by your urologist (or uro-oncologist).
Chemotherapy is not used in kidney cancer. The current medical treatment for kidney cancer is based on pills that stop blood supply to the cancer, which slows or stops the growth of the tumour, and sometimes causes it to shrink. These pills target specific signals within the cancer, and are also called “targeted therapies”. Other names for this group of drugs are “anti-angiogenic therapies” and “tyrosine kinase inhibitors”. While these pills are not chemotherapy, they do have side effects. The tyrosine kinase inhibitors used to treat kidney cancer are: axitinib, pazopanib, sorafenib, sunitinib. Many other drugs in this family are in development and at various stages or research and approvals. Newer drugs include cabozantinib and lenvatinib:
A second group of medicines for kidney cancer work by blocking a different signal (“mTOR inhibitors”). These are usually used only if the pills that block the blood supply have stopped working. The mTOR inhibitors used to treat kidney cancer are everolimus and temsirolimus.
New clinical trials are underway to determine if other types of cell signalling can be turned off to prevent the growth of kidney cancer. One potential inhibitor is a MET inhibitor that works in other types of cancer and is particularly important in Papillary Renal Cell Carcinoma.
Other new types of inhibitors are in clinical trials for kidney cancer.
Before 2006, immunotherapy with interleukin-2 (IL-2) and alpha-interferon was commonly used to treat kidney cancer that had spread to other parts of the body (metastatic kidney cancer). These drugs worked for some people by activating killer T cells, which are the part of the body’s immune system that destroys cancer cells. New kinds of immune therapy are being tested in clinical trials in kidney cancer. For more information about the newer immune therapies, click here.
Uses high-energy radiation to kill cancer cells. Radiation can be very helpful if the cancer causes a lot of problems in one location, e.g. cancer in the bone causing pain, cancer in the kidney causing bleeding, cancer in the brain causing swelling. Radiation is predominantly used as a means of controlling symptoms (e.g. pain).
Palliation doesn’t mean the “end of the road” or that the cancer is in its terminal stages. Palliative care is all the treatments that your team recommend to improve your symptoms and improve your quality of life. Your family doctor, your medical oncologist and your other doctors will help you with this. Sometimes palliative care physicians and nurses are consulted, and they can often provide specialised advice. Palliative treatment can improve quality of life by alleviating symptoms associated with advanced cancer.
This is a question that kidney cancer researchers around the world are looking to answer. The truth is that we have a great deal of hope, but we currently have more questions than answers. The only way to find out the answers is to design and run clinical trials and to share the information widely.
For now, it’s best to remember that not everything that you read in the newspapers is factually correct. What makes for a good newspaper article is not necessarily true.
In future years we hope to better understand:
Everyone wants the best health care for themselves and their loved ones. If there are no suitable standard medical therapies available, “alternative” therapies might be proposed by well-intentioned friends, relatives or internet web-pages.
These are called “alternative” because they have not been scientifically proven to shrink cancers or help patients. Worse still, they might have been proven not to help or to even cause harm. Examples of unhelpful or harmful alternative “treatments” include mega-dose vitamins, herbal products or extreme diets. A good website to check if an alternative “therapy” has been debunked is www.quackwatch.org.
Some alternative therapies can interfere with medicines normally prescribed by a doctor, causing harm to the patient. So it’s important to inform your doctor or nurse if you are considering these therapies.
On the other hand, complementary therapies can “complement” established medical treatments, improving quality of life and symptoms. These include mindfulness meditation, relaxation techniques, remedial massage therapy, psychotherapy, prayer, yoga, acupressure and acupuncture. If there were any chance that the kidney cancer has spread to bones, chiropractic or osteopathy would not be a good idea.
This can be a difficult question for you and your doctor to discuss. There are a number of questions that you can ask your doctor, and a number of things to keep in mind.
When one hears about the statistics of a cancer, or the benefit of a treatment, it is important to remember that these are statistics based upon the experience of often hundreds of patients. What will happen to you, a single person, can only be very vaguely inferred from these statistics. Some peoples’ cancers are very aggressive and treatment fails them. Other people have very slow-growing cancers, or have substantial benefits from taking a drug. One way that your doctor might give you some estimate of what your future might hold is to talk about worst-case and best-case scenarios.
It is also important to remember that no-one has a crystal ball, and that any prediction of the future can only be a best guess. As you develop a relationship with your doctor and health care team over time, this will also allow you to get a better understanding of how your particular cancer journey is unfolding. Many of the issues discussed above can influence prognosis, and understanding these can be important to help predict what your future might hold.