What is Kidney Cancer?
Cancer that forms in tissues of the kidneys is termed as kidney cancer. Kidney cancer includes renal cell carcinoma (cancer that forms in the lining of very small tubes in the kidney that filter the blood and remove waste products) and renal pelvis carcinoma (cancer that forms in the center of the kidney where urine collects). It also includes Wilms tumor, which is a type of kidney cancer that usually develops in children under the age of 5.
Kidney cancer is cancer that originates in the kidneys. Your kidneys are two bean-shaped organs, each about the size of your fist. They're located behind your abdominal organs, with one kidney on each side of your spine.
The incidence of kidney cancer seems to be increasing, though it isn't clear why. Many kidney cancers are detected during procedures for other diseases or conditions. Imaging techniques such as computerized tomography (CT) are being used more often, which may lead to the discovery of more kidney cancers.
Causes of Kidney Cancer
The majority of the cancers appear in people between the ages of 40 and 70 and in men about twice as frequently as women. Smokers are far more likely to develop cancer than non-smokers. It is estimated that if all smokers quit, the appearance of certain kidney cancers would drop by half. Pain killers, such as over the counter medications containing phenacetin, have been linked to kidney cancers. These were pulled from the market 20 or more years ago but some older people who used them may still be at risk.
High fat diets, excessive weight and hypertension are risk factors. Workers exposed to asbestos or cadmium, an ingredient in inks and paints, are at a slightly higher risk. Genetics play a role. People who have a history of kidney cancer in their immediate families are at higher risk, especially if they smoke or have been exposed to the aforementioned chemicals.
Kidney cancer can be caused by some rare inherited conditions such as those listed below. People who have these conditions have a much higher risk for getting kidney cancer, but they account for only a small portion of cases overall.
Von Hippel-Lindau disease
Hereditary papillary renal cell carcinoma
Hereditary leiomyoma-renal cell carcinoma
Hereditary renal oncocytoma
If you know that you have one of these, it is important that you see your doctor often.
Symptoms of Kidney Cancer
In many cases, people may have no early symptoms of kidney cancer. As the tumor grows larger, symptoms may appear. You may have one or more of these kidney cancer symptoms:
Blood in your urine
A lump in your side or abdomen
A loss of appetite
A pain in your side that doesn't go away
Weight loss that occurs for no known reason
Fever that lasts for weeks and isn't caused by a cold or other infection
Swelling in your ankles or legs
Kidney cancer that spreads to other parts of your body may cause other symptoms, such as:
Shortness of breath
Coughing up blood
Kidney Cancer Treatment
Surgery is the most common treatment for kidney cancer. Surgical removal of all or part of the kidney (nephrectomy) is recommended. This may include removing the bladder or surrounding tissues or lymph nodes. In some patients, surgery to remove a small number of tumors that have spread (metastases) may be helpful.
Radiation therapy usually does not work for renal cell carcinoma so it is not often used. Hormone treatments may reduce the growth of the tumor in some cases.
Chemotherapy is generally not effective for treating renal cell carcinoma. The drug interleukin-2 (IL-2), which works by helping the body’s own immune system kill the cancer cells, may help a small number of patients, but it is very toxic. Other chemotherapy drugs have been used, but patients generally do not live long once the disease has spread outside the kidney.
Newer therapies include sorafenib (Nexavar), sunitinib (Sutent), and temsirolimus (Torisel). The biologic drug bevacizumab (Avastin) has also been used.
A cure is unlikely unless all of the cancer is removed with surgery.
Kidney Cancer Surgery
The most appropriate type of surgery for your situation will depend on the size of the cancer and whether or not it has spread, as well as your age and general health. It’s important to discuss any operation fully with your surgeon before you have it.
Radical nephrectomy: The most common type of surgery for kidney cancer is a radical nephrectomy. The surgeon removes the entire affected kidney and some surrounding tissue. This operation usually involves a cut (incision) made between the lower ribs on the side of the tumour. The surgeon may also remove some, or all, of the lymph nodes close to the kidney to check if they contain cancer.
It’s possible to live a completely normal life with just one kidney; it will do the work usually shared by two kidneys. But, removing a kidney is a big operation and you need to be reasonably fit. This means that this type of surgery isn’t suitable for everyone. In some cases people who aren’t fit enough to have standard surgery may be able to have an operation using one of the newer surgical techniques that are being developed, such as keyhole surgery.
Partial nephrectomy: Instead of taking out all of the kidney, the surgeon will sometimes only remove the tumour and the part of the kidney surrounding it. This is called a partial nephrectomy or nephron-sparing surgery and it’s usually only possible if the tumour is smaller than 4cm.
A partial nephrectomy may also be used if it’s important to try to keep the affected kidney, for example if you have only one kidney or have kidney disease. It may also be used if you have an inherited form of kidney cancer that increases your risk of cancer developing in the other kidney.
Keyhole surgery: In some situations, it may be possible to have keyhole or laparoscopic surgery to remove some, or your entire kidney. In this type of surgery only small openings are made instead of one larger cut (incision). The surgeon uses a special instrument called a laparoscope to see and work inside the belly (abdomen).
Types of Kidney Cancer
There are a number of different types of cancer than can affect the kidneys. The most common type is known as renal cell carcinoma (RCC), which accounts for about 90% of all kidney cancers.
Rarer types of kidney cancer include:
Transitional cell cancer: develops in the lining of the kidneys and usually affects older men who are 50 years of age or over
Wilms’ tumour: a rare type of kidney cancer that affects children
Transitional Cell Carcinoma: About 6% to 7% of kidney cancers begin not in the kidney itself, but in the renal pelvis, the point where the kidney joins the tube that carries urine form the kidney to the bladder (ureter). These tumors are called transitional cell carcinomas and are made up of cancer cells different from those that characterize RCC. Research indicates these tumors are caused by cigarette smoking.
Wilms' Tumor: A relatively rare form of kidney cancer, Wilms' tumor (also known as nephroblastoma) accounts for about 5% to 8% of kidney tumors in children. It occurs in about 7 out of every 1 million children around the world per year, regardless of race, and is thought to be caused by genetic mutation that causes abnormal growth within the tubules of the kidney nephrons. The disease occurs equally in boys and girls. It typically first appears in children between 2 and 5 years of age but has been known to occur rarely in adolescents as old as 15.
Wilms' tumor can arise anywhere within the kidney's tissues. Untreated, it can spread to the veins, lymph nodes, adrenal glands, large or small bowel, and liver. Fortunately, advances in radiation and chemotherapy over the past few decades, pediatric anesthesia, and surgery have made Wilms' tumor one of the most curable of all childhood cancers. Today the 5-year survival rate approaches 90%.
Recovery from Kidney Cancer Surgery
It takes time to heal after surgery for kidney cancer, and recovery is different for each person. After the procedure, you may feel uncomfortable, tired, and weak. However, medicine can usually control the pain, and you should discuss the plan for pain relief with your doctor or nurse before surgery. Afterward, your doctor can adjust the plan if more pain relief is needed.
The healthcare team will need to watch you for signs of problems by:
Monitoring the amount of fluid that you take in and the amount of urine produced
Looking for signs of bleeding, infection, or other problems requiring immediate treatment
Ordering lab tests.