Renal cancer is cancer that originates in the kidneys. The two most common types of kidney cancer are renal cell carcinoma (RCC) and transitional cell carcinoma (TCC, also known as urothelial cell carcinoma) of the renal pelvis. These names reflect the type of cell from which the cancer developed. The different types of kidney cancer (such as RCC and UCC) develop in different ways, meaning that the diseases have different long term outcomes, and need to be staged and treated in different ways. RCC is responsible for approximately 80% of primary renal cancers, and UCC accounts the majority of the remainder.
In adults, the most common type of kidney cancer is renal cell carcinoma. Other less common types of kidney cancer can occur. Young children are more likely to develop a kind of kidney cancer called Wilms' tumor.
Renal cancer rarely causes signs or symptoms in its early stages. In the later stages, signs and symptoms may include:
- Intermittent fever and heavy sweating
- Mass in the abdomen
- Loss of appetite
- Persistent pain in the abdomen
It's not clear what causes renal cell carcinoma.
Doctors know that kidney cancer begins when some kidney cells acquire mutations in their DNA. The mutations tell the cells to grow and divide rapidly. The accumulating abnormal cells form a tumor that can extend beyond the kidney. Some cells can break off and spread (metastasize) to distant parts of the body.
Factors that can increase the risk of kidney cancer include:
- Older age
- High blood pressure (hypertension)
- Treatment for kidney failure.
- Certain inherited syndromes, including those who have von Hippel-Lindau disease, Birt-Hogg-Dube syndrome, tuberous sclerosis and familial papillary renal cell carcinoma.
Taking steps to improve your health may help reduce your risk of renal cancer. To reduce your risk, try to:
- Quit smoking. If you smoke, quit. Many options for quitting exist, including support programs, medications and nicotine replacement products. Tell your doctor you want to quit, and discuss your options together.
- Maintain a healthy weight. Work to maintain a healthy weight. If you're overweight or obese, reduce the number of calories you consume each day and try to exercise most days of the week. Ask your doctor about other healthy strategies to help you lose weight.
- Control high blood pressure. Ask your doctor to check your blood pressure at your next appointment. If your blood pressure is high, you can discuss options for lowering your numbers. Lifestyle measures such as exercise, weight loss and diet changes can help. Some people may need to add medications to lower their blood pressure.
The health care provider will perform a physical exam. This may reveal:
- Mass or swelling of the abdomen
- A varicocele in the male scrotum
Tests and procedures used to diagnose kidney cancer include:
- Blood and urine tests.Tests of your blood and your urine may give your doctor clues about what's causing your signs and symptoms.
- Imaging tests. Imaging tests allow your doctor to visualize a kidney tumor or abnormality. Imaging tests might include ultrasound, computerized tomography (CT) scan or magnetic resonance imaging (MRI).
- Removing a sample of kidney tissue (biopsy). In rare cases, your doctor may recommend a procedure to remove a small sample of cells (biopsy) from a suspicious area of your kidney. The sample is tested in a lab to look for signs of cancer.
- Intravenous pyelogram (IVP)
- Liver function tests
- Renal arteriography
The following tests may be done to see if the cancer has spread:
- Abdominal CT scan
- Abdominal MRI
- Bone scan
- Chest x-ray
- Chest CT scan
- PET scan
Renal cancer staging:
Once your doctor identifies a kidney lesion that might be kidney cancer, the next step is to determine the extent (stage) of the cancer. Staging tests for kidney cancer may include additional CT scans or other imaging tests your doctor feels are appropriate.
Then your doctor assigns a number, called a stage, to your cancer. Renaly cancer stages include:
- Stage I. At this stage, the tumor can be up to 2 3/4 inches (7 centimeters) in diameter. The tumor is confined to the kidney.
- Stage II. A stage II kidney cancer is larger than a stage I tumor, but it's still confined to the kidney.
- Stage III. At this stage, the tumor extends beyond the kidney to the surrounding tissue and may also have spread to a nearby lymph node.
- Stage IV. Cancer spreads outside the kidney, to multiple lymph nodes or to distant parts of the body, such as the bones, liver or lungs.
Survival rates are often used by doctors as a standard way of discussing a person’s prognosis (outlook). Some people with cancer may want to know the survival statistics for people in similar situations, while others may not find the numbers helpful, or may even not want to know them.
The 5-year survival rate refers to the percentage of patients who live at least 5 years after their cancer is diagnosed. Of course, many people live much longer than 5 years (and many are cured). Also, some people die from causes other than their cancer. In order to get 5-year survival rates, doctors have to look at people who were treated at least 5 years ago. Treatments for kidney cancer have changed in recent years, which may result in a better outlook for people now being diagnosed with kidney cancer.
Survival rates are often based on previous outcomes of large numbers of people who had the disease, but they cannot predict what will happen in any person’s case. Many other factors can affect a person’s outlook, such as the grade of the cancer, the treatment received, and the patient’s age and overall health. Your doctor can tell you what may apply better to you, as he or she is familiar with your situation.
The best approach for you may depend on a number of factors, including general health, the kind of kidney cancer you have, whether the cancer has spread and your preferences for treatment.
Surgery is the standard of care for the majority of kidney cancers. Surgical procedures used to treat kidney cancer include:
- Removing the affected kidney (Nephrectomy). Radical nephrectomy involves the removal of the kidney, a border of healthy tissue and the adjacent lymph nodes. The adrenal gland also may be removed. Nephrectomy can be an open operation, meaning the surgeon makes one large incision to access your kidney. Or nephrectomy can be done laparoscopically, using several small incisions to insert a video camera and tiny surgical tools. The surgeon watches a video monitor to perform the nephrectomy. In some cases, this surgery can be done robotically, which means the surgeon uses hand controls that tell a robot how to maneuver surgical tools to perform the operation.
- Removing the tumor from the kidney (Nephron-sparing surgery). During this procedure, also called partial nephrectomy, the surgeon removes the tumor and a small margin of healthy tissue that surrounds it, rather than removing the entire kidney. Nephron-sparing surgery can be an open procedure, or it may be performed laparoscopically or with robotic assistance. Nephron-sparing surgery is a common treatment for small kidney cancers. It may also be an option if you have only one kidney. When nephron-sparing surgery is possible, it's generally preferred over radical nephrectomy since retaining as much kidney tissue as possible may reduce your risk of later complications, such as kidney disease and the need for dialysis.
The type of surgery your doctor recommends will be based on your cancer and its stage, as well as your health. Surgery carries a risk of bleeding and infection.
Treatments when surgery isn't possible:
Surgery isn't an option. In these situations, kidney cancer treatments may include:
- Treatment to freeze cancer cells (Cryoablation). During cryoablation, a special needle is inserted through your skin and into your kidney tumor using X-ray guidance. Gas in the needle is used to cool down or freeze the cancer cells. There are few long-term data about the safety and efficacy of cryoablation for kidney cancer. It's typically reserved for people who can't undergo other surgical procedures and those who have small kidney tumors.
- Treatment to heat cancer cells (Radiofrequency ablation). During radiofrequency ablation, a special needle is inserted through your skin and into your kidney tumor using X-ray guidance. An electrical current is run through the needle and into the cancer cells, causing the cells to heat up or burn. There are few long-term data about the safety and efficacy of radiofrequency ablation for kidney cancer. Radiofrequency ablation may be an option for people who can't undergo other surgical procedures and those with small kidney tumors.
Treatments for advanced and recurrent kidney cancer
Kidney cancer that recurs and kidney cancer that spreads to other parts of the body may not be curable, but may be controlled with treatment. In these situations, treatments may include:
- Surgery to remove as much of the kidney tumor as possible. Even when surgery can't remove all of your cancer, in some cases it may be helpful to remove as much of the cancer as possible. Surgery may also be used to remove cancer that has spread to another area of the body.
- Drugs that use your immune system to fight cancer (Biological therapy). Biological therapy (immunotherapy) uses your body's immune system to fight cancer. Drugs in this category include interferon and aldesleukin (Proleukin), which are synthetic versions of chemicals made in your body. Side effects of these drugs include chills, fever, nausea, vomiting and loss of appetite.
- Treatment that targets specific aspects of your cancer (Targeted therapy). Targeted treatments block specific abnormal signals present in kidney cancer cells that allow them to proliferate. These drugs have shown promise in treating kidney cancer that has spread to other areas of the body.
The targeted drugs such as axitinib (Inlyta), bevacizumab (Avastin), pazopanib (Votrient), sorafenib (Nexavar) and sunitinib (Sutent) block signals that play a role in the growth of blood vessels that provide nutrients to cancer cells and allow cancer cells to spread. Temsirolimus (Torisel) and everolimus (Afinitor) are targeted drugs that block a signal that allows cancer cells to grow and survive.
Targeted therapy drugs can cause side effects, such as a rash that can be severe, diarrhea and fatigue.
- Radiation therapy. Radiation therapy uses high-powered energy beams, such as X-rays, to kill cancer cells. Radiation therapy is sometimes used to control or reduce symptoms of kidney cancer that has spread to other areas of the body, such as the bones.
Refer to Research Publications.