Kidney Cancer Causes, Types, Symptoms, Diagnosis, Treatment, Prevention

Kidney Cancer Causes, Types, Symptoms, Diagnosis, Treatment, Prevention


The Kidneys


The kidneys are two reddish-brown, bean-shaped organs located just above the waist, one on each side of the spine. They are part of the urinary system. Their main function is to filter blood and produce urine to rid the body of waste. As blood flows through the kidneys, they remove waste products and unneeded water. 

The resulting liquid, urine, collects in the middle of each kidney in an area called the renal pelvis. Urine drains from each kidney through a long tube, the ureter, into the bladder, where it is stored. Urine leaves the body through another tube, called the urethra.

The kidneys also produce substances that help control blood pressure and regulate the formation of red blood cells.

What Is Cancer?


Cancer is a group of many different diseases that have some important things in common. They all affect cells, the body's basic unit of life. To understand cancer, it is helpful to know about normal cells and about what happens when cells become cancerous.

The body is made up of many types of cells. Normally, cells grow and divide to produce more cells only when the body needs them. This orderly process helps keep the body healthy. Sometimes cells keep dividing when new cells are not needed. A mass of extra tissue forms, and this mass is called a growth or tumor. Tumors can be benign or malignant.

Benign tumors are not cancer. They often can be removed and, in most cases, they do not come back. Cells in benign tumors do not spread to other parts of the body. Most important, benign tumors are rarely a threat to life.

Malignant tumors are cancer. Cells in malignant tumors are abnormal and divide without control or order. These cancer cells can invade and destroy the tissue around them. Also, cancer cells can break away from a malignant tumor and enter the bloodstream or lymphatic system. This process is how cancer spreads from the original (primary) tumor to form new tumors in other parts of the body. The spread of cancer is called metastasis.

Kidney Cancer


Several types of cancer can develop in the kidney. This booklet discusses renal cell cancer, the most common form of kidney cancer in adults. Transitional cell cancer (carcinoma), which affects the renal pelvis, is a less common form of kidney cancer. It is similar to cancer that occurs in the bladder and is often treated like bladder cancer. Wilms' tumor, the most common type of childhood kidney cancer, is different from kidney cancer in adults. The Cancer Information Service can provide information about transitional cell cancer and Wilms' tumor.

As kidney cancer grows, it may invade organs near the kidney, such as the liver, colon, or pancreas. Kidney cancer cells may also break away from the original tumor and spread (metastasize) to other parts of the body. When kidney cancer spreads, cancer cells may appear in the lymph nodes. For this reason, lymph nodes near the kidney may be removed during surgery. If the pathologist finds cancer cells in the lymph nodes, it may mean that the disease has spread to other parts of the body. Kidney cancer may spread and form new tumors, most often in the bones or lungs. The new tumors have the same kind of abnormal cells and the same name as the original (primary) tumor in the kidney. For example, if kidney cancer spreads to the lungs, the cancer cells in the lungs are kidney cancer cells. The disease is metastatic kidney cancer; it is not lung cancer.

Causes of Kidney Cancer


Kidney disease


People with kidney failure have to have their blood filtered by a machine about twice a week. This is called dialysis. People having long term kidney dialysis have an increased risk of developing kidney cysts and this increases the risk of kidney cancer. The longer you have dialysis, the greater your risk of kidney cancer. But this is probably because you needed dialysis due to kidney disease. The dialysis itself is not directly related to the cancer risk.

Obesity and height


Being very overweight (obese) increases the risk of getting kidney cancer. A Cancer Research UK study published in 2011 found that being overweight or obese causes around a quarter of kidney cancers (24%). Obese means that your body mass index is 30 or higher. Or more roughly, that your weight is at least 25% higher than the top of the healthy range for your height. Body mass index (BMI) is worked out by comparing your height and weight. Being overweight causes changes in hormones in the body, particularly for women. It could be this change in the body’s hormone balance that increases the risk of kidney cancer.

There is information about the right weight for you on this website. And you can find information about healthy eating on our news and resources website.

A large UK study has shown that taller women may be at a higher risk of developing kidney cancer than shorter women.

Smoking


If you smoke, your risk of getting kidney cancer goes up. On average, smokers have a 50% increase in risk. But the risk increases with the number of cigarettes that you smoke. People who smoke more than 20 cigarettes a day can have up to double the risk of the most common type of kidney cancer (renal cell cancer) compared to non smokers. Smokers also have up to 3 times the risk of developing cancer of the central area of the kidney (the renal pelvis) compared to non smokers. But your risk falls if you stop smoking and after 10 years is the same as a non smoker.

Faulty genes and inherited conditions


A small number of people inherit faulty genes that increase their risk of developing kidney cancer and other medical conditions. Changes in the DNA that makes up the faulty gene make the gene behave in an abnormal way. Cancers caused by these faulty genes are called  hereditary or familial kidney cancer. Scientists are finding out which genes carry these mistakes in the DNA. In the future this could help doctors predict who is at risk of getting hereditary kidney cancer.

People with kidney cancer who have these genetic conditions often have cancer in both kidneys (bilateral kidney cancer). They may also have several tumours in each kidney. They often develop the cancer at a younger age than people with non inherited cancers. For more information about these rare types of kidney cancer, look at the page for kidney cancer organisations.

The inherited conditions that increase the risk of kidney cancer include

  • Von Hippel-Lindau (VHL) syndrome
  • Tuberous sclerosis
  • Birt-Hogg-Dube syndrome
  • Hereditary non VHL clear cell and papillary renal cell cancer

Von Hippel-Lindau (VHL) syndrome


Von Hippel-Lindau syndrome is an inherited cancer syndrome. The VHL gene runs through affected families. People who carry the gene have an increased risk of developing several quite rare cancers in the brain, spine, pancreas, eyes and inner ear. About 40% of people with vHL get kidney cancer.

Tuberous sclerosis


Tuberous sclerosis (TS) is another condition caused by a faulty gene. About 1 in 3 cases are inherited. But the other 2 out of 3 occur because the gene has mutated in those people for the first time. It can cause skin, brain and heart problems, as well as kidney disease. People with TS have an increased risk of kidney cysts and kidney cancer.

Birt-Hogg-Dube syndrome


Birt-Hogg-Dube syndrome is another inherited condition. It causes many non cancerous (benign) tumours to develop in the hair follicles of the skin. These usually develop on the face, neck and trunk. People who carry this gene have an increased risk of kidney cancer.

Hereditary clear cell and papillary renal cell cancer


Hereditary clear cell kidney cancer and hereditary papillary kidney cancers are both caused by inherited faulty genes. They are dominant genetic conditions. This means that you only have to inherit the faulty gene from one parent. Even so, they are both very rare.

Family history


Studies have shown that people with a first degree relative diagnosed with kidney cancer have roughly double the risk of developing renal cell carcinoma themselves. A first degree relative is a parent, brother or sister, or your child.

High blood pressure


Some research studies have found a link between high blood pressure or high blood pressure medicines and kidney cancer. It is more likely that high blood pressure is the link, rather than the medicines. High blood pressure is a known risk factor for kidney disease in general.

Alcohol


The risk of kidney cancer is slightly lower in people who drink alcohol compared to non drinkers. But alcohol increases the risk of several other types of cancer.

Thyroid cancer


People who have had thyroid cancer have a risk of kidney cancer that is 2 to 7 times higher than people who have not had thyroid cancer. It may be due to gene changes that are common to both cancers.

Radiotherapy for cancer


Men treated with radiotherapy for testicular cancer have double the risk of kidney cancer compared to men in the general population. But the risk is still small. The risk after radiotherapy for testicular cancer gradually rises and after 30 years is increased by almost three times. 

Women who have had radiotherapy for cancer of the neck of the womb (cervical cancer) have their risk of kidney cancer increased by almost a third. After 30 years the risk is almost double compared to that of women in the general population.

Hysterectomy


There is limited evidence that hysterectomy may increase the risk of kidney cancer.

Mild painkillers


Some mild painkilling drugs have been linked to increased kidney cancer risk. One drug that could definitely increase the risk was phenacetin, but this has been taken off the market in the UK. Some other types of painkillers called non steroidal anti inflammatory drugs (NSAIDs) may increase the risk of kidney cancer slightly, including ibuprofen (Nurofen). It is unlikely that occasional use or low dose use would be harmful.

Kidney Cancer Symptoms


In its early stages, kidney cancer usually causes no obvious signs or troublesome symptoms. However, as a kidney tumor grows, symptoms may occur. These may include:

  • Blood in the urine. Blood may be present one day and not the next. In some cases, a person can actually see the blood, or traces of it may be found in urinalysis, a lab test often performed as part of a regular medical checkup.
  • A lump or mass in the kidney area.

Other less common kidney cancer symptoms may include:

  • Fatigue;
  • Loss of appetite;
  • Weight loss;
  • Recurrent fevers;
  • A pain in the side that doesn't go away; and/or
  • A general feeling of poor health.

High blood pressure or a lower than normal number of red cells in the blood (anemia) may also signal a kidney tumor; however, these symptoms occur less often.

These symptoms may be caused by cancer or by other, less serious problems such as an infection or a cyst. Only a doctor can make a diagnoses. People with any of these symptoms may see their family doctor or a urologist, a doctor who specializes in diseases of the urinary system. Usually, early cancer does not cause pain; it is important not to wait to feel pain before seeing a doctor.

In most cases, the earlier cancer is diagnosed and treated, the better a person's chance for a full recovery.

Diagnosis for Kidney Cancer


To find the cause of symptoms, the doctor asks about the patient's medical history and does a physical exam. In addition to checking for general signs of health, the doctor may perform blood and urine tests. The doctor may also carefully feel the abdomen for lumps or irregular masses.

The doctor usually orders tests that produce pictures of the kidneys and nearby organs. These pictures can often show changes in the kidney and surrounding tissue. For example, an IVP (intravenous pyelogram) is a series of x-rays of the kidneys, ureters, and bladder after the injection of a dye. The dye may be placed in the body through a needle or a narrow tube called a catheter. The pictures produced can show changes in the shape of these organs and nearby lymph nodes.

Another test, arteriography, is a series of x-rays of the blood vessels. Dye is injected into a large blood vessel through a catheter. X-rays show the dye as it moves through the network of smaller blood vessels in and around the kidney.

Other imaging tests may include CT scan, MRI, and ultrasonography, which can show the difference between diseased and healthy tissues.

If test results suggest that kidney cancer may be present, a biopsy may be performed; it is the only sure way to diagnose cancer. During a biopsy for kidney cancer, a thin needle is inserted into the tumor and a sample of tissue is withdrawn. A pathologist then examines the tissue under a microscope to check for cancer cells.

Once kidney cancer is diagnosed, the doctor will want to learn the stage, or extent, of the disease. Staging is a careful attempt to find out whether the cancer has spread and, if so, what parts of the body are affected. This information is needed to plan a patient's treatment.

To stage kidney cancer, the doctor may use additional MRI and x-ray studies of the tissues and blood vessels in and around the kidney. The doctor can check for swollen lymph nodes in the chest and abdomen through CT scans. Chest x-rays can often show whether cancer has spread to the lungs. Bone scans reveal changes that may be a sign that the cancer has spread to the bones.

A person who needs a biopsy may want to ask the doctor some of the following questions:

  • How long will it take? Will I be awake? Will it hurt?
  • How soon will I know the results?
  • If I do have cancer, who will talk with me about treatment? When?

Methods of Kidney Cancer treatment


People with kidney cancer may have surgery, arterial embolization, radiation therapy, biological therapy, or chemotherapy. Some may have a combination of treatments.

At any stage of disease, people with kidney cancer may have treatment to control pain and other symptoms, to relieve the side effects of therapy, and to ease emotional and practical problems. This kind of treatment is called supportive care, symptom management, or palliative care.

A patient may want to talk to the doctor about taking part in a clinical trial, a research study of new treatment methods. The section on "The Promise of Cancer Research" has more information about clinical trials.

Surgery


Surgery is the most common treatment for kidney cancer. It is a type of local therapy. It treats cancer in the kidney and the area close to the tumor.

An operation to remove the kidney is called a nephrectomy. There are several types of nephrectomies. The type depends mainly on the stage of the tumor. The doctor can explain each operation and discuss which is most suitable for the patient:

  • Radical nephrectomy: Kidney cancer is usually treated with radical nephrectomy. The surgeon removes the entire kidney along with the adrenal gland and some tissue around the kidney. Some lymph nodes in the area also may be removed.
  • Simple nephrectomy: The surgeon removes only the kidney. Some people with Stage I kidney cancer may have a simple nephrectomy.
  • Partial nephrectomy: The surgeon removes only the part of the kidney that contains the tumor. This type of surgery may be used when the person has only one kidney, or when the cancer affects both kidneys. Also, a person with a small kidney tumor (less than 4 centimeters) may have this type of surgery.
People may want to ask the doctor these questions before having surgery:
  • What kind of operation do you recommend for me? Do I need any lymph nodes removed? Why?
  • What are the risks of surgery? Will I have any long-term effects? Will I need dialysis?
  • Should I store some of my own blood in case I need a transfusion?
  • How will I feel after the operation?
  • How long will I need to stay in the hospital?
  • When can I get back to my normal activities?
  • How often will I need checkups?
  • Would a clinical trial be appropriate for me?

Arterial embolization


Arterial embolization is a type of local therapy that shrinks the tumor. Sometimes it is done before an operation to make surgery easier. When surgery is not possible, embolization may be used to help relieve the symptoms of kidney cancer.

The doctor inserts a narrow tube (catheter) into a blood vessel in the leg. The tube is passed up to the main blood vessel (renal artery) that supplies blood to the kidney. The doctor injects a substance into the blood vessel to block the flow of blood into the kidney. The blockage prevents the tumor from getting oxygen and other substances it needs to grow.

People may want to ask the doctor these questions before having arterial embolization:
  • Why do I need this procedure?
  • Will I have to stay in the hospital? How long?
  • What are the risks and side effects?
  • Would a clinical trial be appropriate for me?

Radiation therapy


Radiation therapy (also called radiotherapy) is another type of local therapy. It uses high-energy rays to kill cancer cells. It affects cancer cells only in the treated area. A large machine directs radiation at the body. The patient has treatment at the hospital or clinic, 5 days a week for several weeks.

A small number of patients have radiation therapy before surgery to shrink the tumor. Some have it after surgery to kill cancer cells that may remain in the area. People who cannot have surgery may have radiation therapy to relieve pain and other problems caused by the cancer.

People may want to ask the doctor these questions before having radiation therapy:
  • Why do I need this treatment?
  • What are the risks and side effects of this treatment?
  • Are there any long-term effects?
  • When will the treatments begin? When will they end?
  • How will I feel during therapy?
  • What can I do to take care of myself during therapy?
  • Can I continue my normal activities?
  • How often will I need checkups?
  • Would a clinical trial be appropriate for me?

Biological therapy


Biological therapy is a type of systemic therapy. It uses substances that travel through the bloodstream, reaching and affecting cells all over the body. Biological therapy uses the body's natural ability (immune system) to fight cancer.

For patients with metastatic kidney cancer, the doctor may suggest interferon alpha or interleukin-2 (also called IL-2 or aldesleukin). The body normally produces these substances in small amounts in response to infections and other diseases. For cancer treatment, they are made in the laboratory in large amounts.

Chemotherapy


Chemotherapy is also a type of systemic therapy. Anticancer drugs enter the bloodstream and travel throughout the body. Although useful for many other cancers, anticancer drugs have shown limited use against kidney cancer. However, many doctors are studying new drugs and new combinations that may prove more helpful. The section on "The Promise of Cancer Research" has more information about these studies.

People may want to ask the doctor these questions before having biological therapy or chemotherapy:
  • Why do I need this treatment?
  • How does it work?
  • What are the expected benefits of the treatment?
  • What are the risks and possible side effects of treatment? What can I do about them?
  • When will treatment start? When will it end?
  • Will I need to stay in the hospital? How long?
  • How will treatment affect my normal activities?
  • Would a clinical trial be appropriate for me?

Kidney Cancer Clinical Trials


Many people with kidney cancer take part in clinical trials (treatment studies). Doctors conduct clinical trials to learn about the effectiveness and side effects of new treatments. In some clinical trials, all patients receive the new treatment. In other trials, doctors compare different therapies by giving the new treatment to one group of patients and the standard therapy to another group.

People who take part in these studies have the first chance to benefit from treatments that have shown promise in early research. They also make an important contribution to medical science.

In clinical trials for kidney cancer, doctors are studying new ways of giving radiation therapy and chemotherapy, new drugs and drug combinations, biological therapies, and new ways of combining various types of treatment. Some trials are designed to study ways to reduce the side effects of treatment and to improve quality of life.

Patients who are interested in taking part in a trial should talk with their doctor.

One way to learn about clinical trials is through PDQ, a computerized resource developed by the National Cancer Institute. PDQ contains information about cancer treatment and about clinical trials in progress throughout the country. The Cancer Information Service can provide PDQ information to patients and the public.

Side effects of Kidney Cancer treatment


Because treatment may damage healthy cells and tissues, unwanted side effects are common. These side effects depend mainly on the type and extent of the treatment. Side effects may not be the same for each person, and they may change from one treatment session to the next. Before treatment starts, the health care team will explain possible side effects and suggest ways to help the patient manage them.

Surgery


It takes time to heal after surgery, and the time needed to recover is different for each person. Patients are often uncomfortable during the first few days. However, medicine can usually control their pain. Before surgery, patients should discuss the plan for pain relief with the doctor or nurse. After surgery, the doctor can adjust the plan if more pain relief is needed.

It is common to feel tired or weak for a while. The health care team watches the patient for signs of kidney problems by monitoring the amount of fluid the patient takes in and the amount of urine produced. They also watch for signs of bleeding, infection, or other problems requiring immediate treatment. Lab tests help the health care team monitor for signs of problems.

If one kidney is removed, the remaining kidney generally is able to perform the work of both kidneys. However, if the remaining kidney is not working well or if both kidneys are removed, dialysis is needed to clean the blood. For a few patients, kidney transplantation may be an option. For this procedure, the transplant surgeon replaces the patient's kidney with a healthy kidney from a donor.

Arterial embolization 


After arterial embolization, some patients have back pain or develop a fever. Other side effects are nausea and vomiting. These problems soon go away.

Radiation therapy 


The side effects of radiation therapy depend mainly on the amount of radiation given and the part of the body that is treated. Patients are likely to become very tired during radiation therapy, especially in the later weeks of treatment. Resting is important, but doctors usually advise patients to try to stay as active as they can.

Radiation therapy to the kidney and nearby areas may cause nausea, vomiting, diarrhea, or urinary discomfort. Radiation therapy also may cause a decrease in the number of healthy white blood cells, which help protect the body against infection. In addition, the skin in the treated area may sometimes become red, dry, and tender. Although the side effects of radiation therapy can be distressing, the doctor can usually treat or control them.

Biological therapy


Biological therapy may cause flu-like symptoms, such as chills, fever, muscle aches, weakness, loss of appetite, nausea, vomiting, and diarrhea. Patients also may get a skin rash. These problems can be severe, but they go away after treatment stops.

Chemotherapy


The side effects of chemotherapy depend mainly on the specific drugs and the amount received at one time. In general, anticancer drugs affect cells that divide rapidly, especially:

  • Blood cells: These cells fight infection, help the blood to clot, and carry oxygen to all parts of the body. When drugs affect blood cells, patients are more likely to get infections, may bruise or bleed easily, and may feel very weak and tired.
  • Cells in hair roots: Chemotherapy can cause hair loss. The hair grows back, but sometimes the new hair is somewhat different in color and texture.
  • Cells that line the digestive tract: Chemotherapy can cause poor appetite, nausea and vomiting, diarrhea, or mouth and lip sores. Many of these side effects can be controlled with drugs.

Nutrition 


Patients need to eat well during cancer therapy. They need enough calories to maintain a good weight and protein to keep up strength. Good nutrition often helps people with cancer feel better and have more energy.

But eating well can be difficult. Patients may not feel like eating if they are uncomfortable or tired. Also, the side effects of treatment, such as poor appetite, nausea, or vomiting, can be a problem. Some patients find that foods do not taste as good during cancer therapy.

The doctor, dietitian, or other health care provider can suggest ways to maintain a healthy diet.


Support for Cancer Patients


Living with a serious illness is not easy. People with cancer and those who care about them face many problems and challenges. Coping with these problems is often easier when people have helpful information and support services. Several useful booklets, including Taking Time 8, are available from the Cancer Information Service.

Friends and relatives can be very supportive. Also, it helps many people to discuss their concerns with others who have or have had cancer. Cancer patients often get together in support groups, where they can share what they have learned about coping with cancer and the effects of treatment. It is important to keep in mind, however, that each person is different. Treatments and ways of dealing with cancer that work for one person may not be right for another -- even if they both have the same kind of cancer. It is always a good idea to discuss the advice of friends and family members with the doctor.

People living with cancer may worry about the future. They may worry about holding their job, caring for their family, or keeping up with daily activities. Concerns about tests, treatments, hospital stays, and medical bills are also common. Doctors, nurses, and other members of the health care team can answer questions about treatment, working, or other activities. They can also discuss outlook (prognosis) and the activity level people may be able to manage. Meeting with a social worker, counselor, or member of the clergy also can be helpful to people who want to talk about their feelings or discuss their concerns. Often, a social worker at the hospital or clinic can suggest groups that can help with rehabilitation, emotional support, financial aid, transportation, or home care. For example, the American Cancer Society has many services for patients and their families. Local offices of the American Cancer Society are listed in the white pages of the telephone directory.

Possible Causes and Prevention


Scientists at hospitals and medical centers all across the country are studying kidney cancer. They are trying to learn what causes this disease and how to prevent it. At this time, scientists do not know exactly what causes kidney cancer, and they can seldom explain why one person gets this disease and another does not. However, it is clear that this disease is not contagious; no one can "catch" kidney cancer from another person.

Researchers study patterns of cancer in the population to look for factors that are more common in people who get kidney cancer than in people who don't get this disease. These studies help researchers find possible risk factors for kidney cancer. It is important to know that most people with these risk factors do not get cancer, and people who do get kidney cancer may have none of these factors.

As with most other types of cancer, studies show that the risk of kidney cancer increases with age. It occurs most often between the ages of 50 and 70. It affects almost twice as many men as women. In addition, kidney cancer is somewhat more common among African American men than White men. Other risk factors for kidney cancer include:

Tobacco use: 


Research shows that smokers are twice as likely to develop kidney cancer as nonsmokers. In addition, the longer a person smokes, the higher the risk. However, the risk of kidney cancer decreases for those who quit smoking.

Obesity: 


Obesity may increase the risk of developing kidney cancer. In several studies, obesity has been associated with increased risk in women. One report suggests that being overweight may be a risk factor for men, too. The reasons for this possible link are not clear.

Occupational exposure: 


A number of studies have examined occupational exposures to see whether they increase workers' chances of developing kidney cancer. Studies suggest, for example, that coke oven workers in steel plants have above-average rates of kidney cancer. In addition, there is some evidence that asbestos in the workplace, which has been linked to cancers of the lung and mesothelium (a membrane that surrounds internal organs of the body), also increases the risk of some kidney cancers.

Radiation: 


Women who have been treated with radiation therapy for disorders of the uterus may have a slightly increased risk of developing kidney cancer. Also, people who were exposed to thorotrast (thorium dioxide), a radioactive substance used in the 1920s with certain diagnostic x-rays, have an increased rate of kidney cancer. However, this substance is no longer in use, and scientists think that radiation accounts for an extremely small percentage of the total number of kidney cancers.

Phenacetin: 


Some people have developed kidney cancer after heavy, long-term use of this drug. This painkilling drug is no longer sold in the United States.

Dialysis: 


Patients on long-term use of dialysis to treat chronic kidney failure have an increased risk of developing renal cysts and renal cancer. Further study is needed to learn more about the long-term effects of dialysis on patients with kidney failure.

Von Hippel-Lindau (VHL) disease:


 Researchers have found that people who have this inherited disorder are at greater risk of developing renal cell carcinoma, as well as tumors in other organs. Researchers have found the gene responsible for VHL, and they believe that the isolation of this gene may lead to improved methods of diagnosis, treatment, and even prevention of some kidney cancers.