Kidney cancer
Kidney cancer seldom causes problems in its early stages. But as a tumor grows, you may notice blood in your urine or experience unintentional weight loss or back pain that doesn't go away. Kidney cancer cells may also spread (metastasize) outside your kidneys to nearby organs as well as to more distant sites in the body. Yet if Kidney cancer is detected and treated early, the chances for a full recovery are good.
Kidneys are two bean-shaped organs, each about the size of your fist. They're located behind your abdomen, one on each side of your spine. Like other major organs in the body, the kidneys can sometimes develop cancer. In adults, the most common type of kidney cancer is renal cell carcinoma (renal adenocarcinoma), which begins in the cells that line the small tubes within your kidneys. Children are more likely to develop a kind of kidney cancer called Wilms' tumor.
Signs and symptoms
Kidney cancer rarely causes signs or symptoms in its early stages. In the later stages, the most common sign of both renal cell and transitional cell cancers is blood in the urine (hematuria). You may notice the blood when you urinate, or your doctor may detect it by urinalysis, a test that specifically checks the contents of your urine. Other possible signs and symptoms may include:
- A pain in the back just below the ribs that doesn't go away
- A mass in the area of the kidneys that's discovered during an examination
- Weight loss
- Fatigue
- Intermittent fever
- Pain in other parts of the body if the cancer has metastasized
Causes
Kidneys are part of the urinary system, which removes waste and excess fluid and electrolytes from your blood, controls the production of red blood cells, and regulates your blood pressure. Inside each kidney are more than a million small filtering units called nephrons. As blood circulates through your kidneys, the nephrons filter out waste products as well as unneeded minerals and water. This liquid waste — urine — flows through two narrow tubes (ureters) into your bladder, where it's stored until it's eliminated from your body through another tube, the urethra.
Renal cell carcinoma, which accounts for most kidney cancers, usually begins in the cells that line the small tubes (tubules) that make up a part of each nephron. In most cases, renal cell tumors grow as a single mass, but you may have more than one tumor in a kidney or develop tumors in both kidneys.
A far less common type of kidney cancer, transitional cell carcinoma, develops in the tissue that forms the tubes connecting the kidneys to the bladder. Transitional cell carcinomas can also begin in the ureters themselves or in the bladder. A rare form of kidney cancer, renal sarcoma, begins in the connective tissue of the kidney.
Treatment
Together, you and your treatment team — which may include a surgeon, a doctor who specializes in disorders of the urinary organs (urologist), a cancer specialist (oncologist) and an oncologist who specializes in treating cancer with radiation (radiation oncologist) — will discuss all of your options. The best approach for you may depend on a number of factors, including your general health, the kind of kidney cancer you have and whether the cancer has spread.
Renal cell carcinoma
Treatments for renal cell carcinoma include:
- Surgical removal. Until recently, the standard treatment for cancer that was confined to the kidney was surgical removal of the entire kidney (radical or simple nephrectomy). In a radical nephrectomy, surgeons remove the kidney along with the adrenal gland that sits atop the kidney, a border of normal tissue and adjacent lymph nodes. A simple nephrectomy involves removing the entire kidney, although not the adrenal gland or lymph nodes. But studies show that removing just the tumor (nephron-sparing surgery), rather than the whole kidney, results in survival rates similar to those of more radical procedures. In addition, people who have nephron-sparing surgery appear less likely to develop chronic kidney failure and are more likely to enjoy a better quality of life than do those who have the whole kidney removed.
Sometimes surgeons may choose to remove the entire kidney because of the extent and the location of the tumor. In that case, laparoscopic nephrectomy may offer advantages over traditional open surgery because it typically results in less postoperative pain, faster recovery time and less scarring. In a laparoscopic procedure, a tiny camera is inserted into your body through a small incision. The camera transmits video images that allow your surgeon to see the kidney in great detail. The surgeon inserts surgical instruments through two or three additional small incisions and performs the operation. The recovery time and side effects of any type of kidney surgery will vary, but it's likely you'll feel tired and weak for a time, even with laparoscopic nephrectomy. - Arterial embolization. In this procedure, a radiologist injects a special material into the main blood vessel leading to the kidney. By clogging this vessel, the tumor is deprived of oxygen and other nutrients. Arterial embolization may be used before an operation or to relieve pain and bleeding when an operation isn't possible. Side effects may include temporary nausea, vomiting or pain.
- Radiation therapy. This therapy uses radiation to kill cancer cells. It's usually used to relieve pain when kidney cancer has spread to the bones. In general, you'll receive radiation treatment at a clinic or hospital on an outpatient basis — often five days a week for several weeks. The effects of radiation are cumulative, and you may become very tired in the last few weeks of treatment. The skin in the treated area may become red, tender or itchy, and you also have other side effects, such as nausea and vomiting.
- Immunotherapy. This treatment uses your body's immune system to fight cancer. An oncologist may administer a substance known as a biological response modifier, such as interferon or interleukin-2. Normally produced by the body, these substances are also made in laboratories. Studies show that people may do better when they're treated with both interferon and surgery, rather than with interferon alone. Biological response modifiers can have serious side effects, including chills, fever, nausea, vomiting and loss of appetite. You may bruise easily after treatment and feel extremely tired. Interleukin-2 and interferon therapies can also affect liver and kidney function. These side effects are often severe, but usually disappear once treatment is stopped.
- Chemotherapy. This therapy, which uses drugs to attack rapidly dividing cells, hasn't proved particularly useful for renal cell carcinoma.
Transitional cell cancer
To treat transitional cell cancer in its early stages, surgeons remove an area surrounding the tumor while trying to save the kidney itself. If the tumor is too large or too centrally located, the kidney and ureter may need to be removed along with the portion of the bladder that's connected to the ureter. This helps decrease the risk of cancer cells spreading to the bladder. Chemotherapy is often used to treat transitional cell cancer that has spread.
Wilms' tumor
Treatment for children with Wilms' tumor depends on the child's age and overall health, the type of tumor and whether the cancer has spread. In many cases, treatment may include surgical removal of the tumor followed by chemotherapy or radiation.
Clinical trials
If kidney cancer has spread, standard treatments are seldom effective. For that reason, you may choose to participate in a clinical trial. These trials test the effectiveness and side effects of new treatments. Those who take part have a chance to receive a treatment that may be promising but not yet widely available. If you're interested in clinical trials, talk to your doctor.
Prevention
Although the following steps may not prevent kidney cancer, they can help reduce your cancer risk and keep you healthier overall:
- Quit smoking. Smokers are nearly twice as likely to develop kidney cancer as nonsmokers are. Talk to your doctor about the best ways to stop smoking.
- Eat more fruits and vegetables. In the past, some studies have shown that a diet rich in fruits and vegetables may help protect against kidney cancer. A 2005 Swedish study looked at which types of produce might offer the most benefits. The study found an overall association between consumption of fruits and vegetables and a lower risk of kidney cancer. Further, the study found the strongest association was for study participants eating bananas and root vegetables, including beets and carrots.
- Stay physically active. An active lifestyle reduces your risk of kidney cancer and helps you lower your blood pressure and maintain a healthy weight. Aim for at least 30 minutes of exercise on most days. If you haven't been active before, start out slowly, and gradually increase the amount of time you exercise. Try to include weight-bearing exercises, such as walking, jogging or dancing as well as some strength-training exercises in your routine. Strength training has been found to reduce stress even more than aerobic exercise does, and it has the added benefit of helping keep your bones strong.
- Maintain a healthy weight. There is a clear link between weighing more than is healthy for you and kidney cancer.
- Reduce or avoid exposure to environmental toxins. If you must work with toxic chemicals, take special precautions such as wearing a mask and heavy gloves.
- Reduce high blood pressure. If you have, or think you may have, high blood pressure — which has been linked to renal cell carcinoma in men — talk to your doctor. Diet and exercise can control high blood pressure in many cases.
Informations obtained from National Institute of Health.